Adding pieces during the offseason can be a tricky thing, especially in baseball, where teammates are forced to deal with each other for far longer periods of time than in any of the other major sports.
Not only must a team take into consideration a player's talent level and what he can offer on the field, but what kind of person that player is comes into play quite often as well.
How will does he fit into the clubhouse dynamic? Does he have the right personality, or will he rub his new teammates the wrong way?
Of course, production breeds success, and success has a way of trumping all. But piecing together a major league roster is an inexact science, for sure.
As teams continue to try and get the formula just right, let's take a look at the best addition that each team has made thus far.
*Note; A team re-signing their own free agents does not count as a new addition. This must be a player who spent 2012 with another organization.
Chase Field in Arizona surrendered the sixth-most home runs per game in baseball in 2012—1.192, according to ESPN—so it makes sense for the Diamondbacks to target pitching that keeps the ball on the ground.
Brandon McCarthy does just that, pitching to a 40.5 percent ground-ball rate in 2012—down from the 46.5 percent mark he posted in 2011.
Even with that decline, McCarthy's 40.5 percent mark would rank third on this year's starting staff behind Trevor Cahill (61.2) and Wade Miley (43.5).
McCarthy will fit right in with the rest of Arizona's starters.
Players with B.J. Upton's combination of power and speed don't come around everyday.
Upton's talent level is through the roof, and while he strikes out too much and has been criticized for seemingly losing focus at times, he's is an excellent fit with the Braves.
He'll make up for some of the run production lost when Chipper Jones retired, and his ability to cause havoc on the basepaths will soften the blow from Michael Bourn's departure.
Upton isn't as good as Bourn defensively, but he'll provide Atlanta with more production at the plate.
For the past five seasons, Upton has averaged 18 home runs, 33 doubles and 39 stolen bases. But he's capable of much gaudier numbers. Consider this: Over the last two months of the 2012 season—a span of 58 games—Upton hit 19 home runs, had 35 extra-base hits and drove in 40 runs.
Coming from Joe Maddon's low-profile clubhouse in Tampa Bay, Upton's transition to a similar clubhouse in Atlanta under Fredi Gonzalez will be rather seamless.
Orioles exec Dan Duquette and the front office are going to be busy between now and the start of spring training.
Things have been very quiet in Baltimore this winter, with the biggest acquisitions being reclamation projects.
Guys like first basemen Conor Jackson and Travis Ishikawa, or outfielders Trayvon Robinson and Jason Pridie, aren't locks to make the major league roster—much less make any substantial impact if they did.
Baltimore will make a move eventually, whether it be to add a veteran starting pitcher to give the rotation some more depth or a more permanent solution at first base, where Chris Davis isn't ideal.
While offensive statistics often rule the day when it comes to judging a player's success, the little things that don't necessarily show up in the box score are often more important that what a player does in a few at-bats per game.
Such is the case of David Ross, the new backup catcher in Boston.
Both 300-game winner Tom Glavine and former Red Sox hurler Derek Lowe were effusive in their praise for Ross when they spoke with Nick Cafardo of the Boston Globe:
"When you saw that David was going to catch you, you got kind of excited," said Derek Lowe, who played with Ross in Atlanta. "He’s outstanding. He reminds me a lot of Varitek. He went over the scouting reports like Tek used to, but he thinks outside the box, too. There were days where he’d make you throw pitches that maybe weren’t in the scouting report, but on that day those pitches took advantage of whatever weakness a certain hitter had. He’s really good. That was a heck of a signing by Boston."
“There’s no question the pitchers are going to love throwing to him,” Glavine said. “He’s an outstanding defensive catcher who throws about as well as anyone I’ve seen from back there. He shuts down a running game. I’m not saying some of the elite base runners can’t steal off him, but he’ll shut down the other guys. You just don’t see teams crazy about running against him.
“He wasn’t your typical backup catcher where you expected a drop-off [offensively] when he started. It seemed every time he played, David did something offensively to help the team, whether it was a home run or a big game-winning hit or moving the runner.”
With Ryan Lavarnway the catcher of the future in Boston, having a veteran like Ross to learn from and bounce ideas off of will be crucial to his development.
When Ross is behind the plate, his ability to calm a pitcher down and get through a rough inning is something that you can't put a price on.
Only two starters on the 2012 Chicago Cubs pitching staff eclipsed the 150 innings mark in 2012: Jeff Samardzija and Travis Wood. The Cubs needed a reliable innings-eater in the middle of the rotation.
Enter Edwin Jackson, who has averaged 193 innings per season for six years, twice breaking the 200-inning mark, both in 2009 and 2010.
Not having to overextend his bullpen, Cubs manager Dale Sveum should see an improvement from his relief corps in 2013—something that shouldn't be too difficult to achieve after they pitched to a 4.49 ERA in 2012, the fourth-highest mark in all of baseball.
A versatile player, Jeff Keppinger is slotted to be the starting third baseman for the Chicago White Sox, but chances are that he'll bounce around the infield over the course of the regular season.
Keppinger doesn't strike out, finishing the season with more RBI than strikeouts seven times during his career.
A smart hitter who knows how to advance runners, he will never be mistaken for a slugger, but he gets on base consistently (he has a career .337 OBP) and, hitting in front of the heart of Chicago's lineup, is a lock to cross the plate quite often in 2013.
The leadoff spot was a major problem for the Cincinnati Reds in 2012, with the players who hit there producing a paltry .208/.254/.327 slash line.
The acquisition of Shin Soo-Choo, who has a career .289/.381/.465 slash line, solves that problem.
He's not a center fielder—though that's where he's going to play—but his presence atop the Reds' lineup is sure to result in a major increase in the team's offensive production.
For all of the big bats in Cincinnati's lineup, the Reds ranked only 21st in baseball last season with 669 runs scored, behind Kansas City and ahead of Cleveland.
Cleveland had been searching for a quality right-handed bat with power to fill a corner outfield spot for awhile, and the Tribe finally got their man in Nick Swisher.
Swisher offers new Indians manager Terry Francona versatility, as the veteran can play all three outfield spots as well as first base.
Of even greater importance for a relatively young Indians team is Swisher's impact in the clubhouse. Beloved by teammates, he is as positive a clubhouse influence as there is in the game.
Adding his affable personality and winning attitude to the mix will breathe new life into a team that desperately needs it.
While Colorado's starting rotation was the worst in baseball last year, its bullpen wasn't too far behind, finishing 28th in the league with a 4.52 ERA.
Wilton Lopez will help to bring that number down in 2013.
Expected to be a primary setup man for closer Rafael Betancourt, Lopez went 6-3 with a 2.17 ERA and 1.04 WHIP, saving 10 games for the Houston Astros in 2012.
Most importantly, for the Rockies, is that Lopez keeps the ball on the ground, inducing a ground ball 55 percent of the time last season, according to FanGraphs.
That ability will come in handy pitching in Coors Field, where fly balls keep going...and going.
Adding the 24 home runs and 88 RBI that Torii Hunter has averaged for more than a decade to a Detroit Tigers lineup that already featured AL MVP Miguel Cabrera and Prince Fielder almost doesn't seem fair.
But Hunter won't only help the Tigers offensively.
One of the elite defensive players of his generation, Hunter's ability to get to balls that others can't will make Detroit's pitching staff, already one of the best in baseball, even better.
Don't let Alex White's numbers fool you.
While he finished the 2012 season with a 2-9 record, 5.51 ERA and 1.68 WHIP over 20 starts for the Colorado Rockies, it's important to remember that he was part of the failed four-man rotation with its wacky pitch counts that the Rockies tried to use last season.
Acquired in the trade that sent Wilton Lopez to the Rockies, White was actually fairly effective down the stretch. After being recalled from the minors in August, White pitched to a 3.51 ERA and 1.56 WHIP over his last 10 starts.
Only 24, White, who has a five-pitch repertoire, will prove to be a solid addition to an Astros rotation that needs as many quality arms as it can get.
It goes without saying that the acquisition of James Shields is the biggest move that the Kansas City Royals have made in years.
Not only does Shields give the Royals their first legitimate front-of-the-rotation arm since Zack Greinke, someone who can take the ball every fifth day and put the team in a position to win, he also helps to change the culture in the clubhouse.
Having been part of contending teams in Tampa Bay, Shields expects to win. He knows what it takes to win at the major league level.
Few, if any, players in the Royals clubhouse can say the same thing.
Remember when I said that adding Torii Hunter to the Tigers' lineup almost wasn't fair.
Adding Josh Hamilton to a lineup that already features Mike Trout and Albert Pujols could result in some record-breaking offensive numbers in Los Angeles this season.
Consider this, from the Twitter account of ESPN's SportsCenter:
Josh Hamilton, Albert Pujols and Mike Trout all ranked in top 15 of the AL last season in HR and OPS. #StackedLineup— SportsCenter (@SportsCenter) December 13, 2012
How about this tweet, from ESPN's Numbers Never Lie:
Who do you pitch to, Pujols or Hamilton?
Or do you walk them both and go after Mark Trumbo, who finished the season with 32 HR and 95 RBI?
There isn't a happy ending for the opposition, regardless of what the eventual decision is.
Two former Cy Young Award winners who have yet to celebrate their 30th birthdays in the same rotation?
That's exactly what the Dodgers now have with Zack Greinke and Clayton Kershaw.
Now throwing in not only a pitcher-friendly park, but a pitcher-friendly division and not being asked to take on the opposition's ace every fifth day, Greinke could give the Dodgers a pair of 20-game winners atop their rotation for the first time since 1969, when Bill Singer and Claude Osteen each hit 20 wins exactly.
The Marlins aren't going to hit a whole lot after gutting the roster, so playing sound defense becomes an even bigger priority.
Acquired from the Blue Jays, Adeiny Hechavarria does just that.
He's got the range to get to anything hit near him, the arm strength to make throws from deep in the hole and the glove to field balls cleanly, helping the solidify the Marlins defense up-the-middle.
Milwaukee's bullpen was terrible in 2012, pitching to a 4.66 ERA—the highest in the majors and a big reason why the Brewers missed the playoffs.
Adding Tom Gorzelanny was a step in the right direction for the unit.
After years as a middling starting pitcher, the Nationals threw the southpaw almost exclusively out of the bullpen (he made one start), and it was a role he performed well in.
Gorzelanny went 4-2 with a 2.90 ERA and 1.30 WHIP in just over 68 innings of work. And while he was effective against batters on both sides of the plate, he's best served as a left-handed specialist out of the bullpen.
After watching its starting rotation go 39-75 with a 5.40 ERA in 2012, the Minnesota Twins knew that adding quality arms was a must.
Vance Worley isn't an ace, but acquiring the 25-year-old right-hander from the Philadelphia Phillies in the Ben Revere trade was a step in the right direction.
Worley, who finished third in the 2011 NL Rookie of the Year voting, has made 46 career starts over parts of the last three seasons, going 17-13 with a 3.56 ERA and 1.35 WHIP—solid numbers to be sure.
When you consider that more than half of those starts came at Citizens Bank Park, one of the more hitter-friendly venues in the game, they become even more impressive.
Being able to pair Worley with Scott Diamond atop the Twins rotation should see those awful 2012 numbers take a step in the right direction in 2013.
The New York Mets had to trade a Cy Young Award-winning pitcher to get him, but for the first time since Mike Piazza left Flushing, the Mets have someone that they can rely on behind the plate.
That's not to say that d'Arnaud is going to put up Piazza-like offensive numbers, because few have ever been able to do that. But the 23-year-old has the quick bat, hand-eye coordination and power to be a .300 hitter with 25-plus home runs on a yearly basis.
He has an excellent throwing arm, and while his defensive skills are still a work in progress, they're far ahead of where Josh Thole was.
Not only will d'Arnaud help the Mets offense, but his ability to call a game will lead to greater success on the mound for New York's pitching staff as well.
Kevin Youkilis doesn't help the New York Yankees get any younger or more athletic, but he's a capable player who fits what the Yankees needed this winter.
He'll be the everyday third baseman in place of the injured Alex Rodriguez, and suprisingly enough, was actually a more productive player at the plate and in the field than A-Rod was in 2012.
A-Rod: .275 BA/.783 OPS, 18 HR, 57 RBI
Youk: .235 BA/.745 OPS, 19 HR, 60 RBI
Youkilis is still a quality defensive third baseman, though you might think otherwise by looking at his .964 fielding percentage, minus-6.2 UZR/150 and minus-1 DRS.
But those numbers are superior to A-Rod's .957 fielding percentage, minus-8.8 UZR and minus-2 DRS, and Youk committed only one more error than A-Rod did in 64 more chances.
His ability to play first base will also come in handy on days when Mark Teixiera needs a day off, and should A-Rod return to the field to reclaim his spot at the hot corner, Youk can serve as part of a platoon at DH.
Oakland needed an upgrade at shortstop, so Billy Beane went out and and landed an eight-time All-Star...with the Seibu Lions.
Hiroyuki Nakajima, 30, was worth taking a gamble on considering the lackluster options available that had major league experience.
Nakajima batted .311 with 29 doubles, 13 homers and 74 RBI in 136 games for the Lions last season. And over an 11-year career in the Pacific League, he's a career .302 hitter with four seasons of 20-plus home runs.
A three-time Gold Glove winner, Nakajima should be a marked improvement from Cliff Pennington and Stephen Drew, who were both underwhelming in Oakland last season.
A seven-time All-Star and owner of a career .301/.347/.444 slash line, Michael Young fills the gaping hole that has been third base for the Philadelphia Phillies over the past few seasons.
A professional hitter, Young knows how to put the ball in play, move runners over and bring runners home when he steps to the plate. He doesn't have tremendous power, but 15-plus home runs are certainly within his reach.
Russell Martin isn't going to hit for a high average, but he's capable of replicating the 23 home runs and 68 RBI that all Pirates catchers combined to produce at the plate in 2012.
A solid defensive catcher as well, Martin's ability to call a game and bring pitchers along through rough spots will prove invaluable in Pittsburgh, especially if über-prospects Gerrit Cole and Jameson Taillon make their major league debuts in 2013.
San Diego hasn't done much this offseason, adding only OF Travis Buck and SP Tyson Ross to the roster.
Ross is slotted into the team's starting rotation, but I refuse to call a guy with a career 2-11 record, 5.33 ERA and 1.60 WHIP a good addition.
The Padres are in desperate need of a quality veteran starter, and there just happens to be a few of those still available on the open market (Kyle Lohse and Shaun Marcum, to name a few).
With new ownership in place, GM Josh Byrnes must be allowed to spend some money and shore up the starting rotation.
Andres Torres returns to the place he's had the greatest success in his major league career, giving the reigning World Series champions some outfield depth.
With a .252/.332/.436 slash line over three years spent with the Giants, Torres will serve as one half of a platoon in left field with Gregor Blanco, getting the start when there's a lefty on the mound.
The Seattle Mariners needed a power batm and they got one in Kendrys Morales, made expendable in Los Angeles after the Angels signed Josh Hamilton—the man that the Mariners coveted most of all.
Morales, 29, provides power and the ability to get on base in the middle of Seattle's lineup, taking pressure off of Jesus Montero to be the primary run producer in the Emerald City and serving as a major upgrade over Justin Smoak at first base.
The Cardinals wanted to add a second left-handed reliever to their bullpen mix alongside Marc Rzepczynski, and they did just that, landing a good one in Randy Choate.
He finished the season in a four-way tie for the most pitching appearances in baseball with 80, the second time in the past three years that Choate appeared in at least 80 games (he led the American League with 85 relief appearances for the Tampa Bay Rays in 2010).
He might not start the regular season in the big leagues, but it won't be long before Wil Myers is producing runs in the middle of the Tampa Bay Rays' lineup.
The key piece in the James Shields trade with the Kansas City Royals, Myers is a tremendous hitter. He has bat speed, great hand-eye coordination and the ability to make adjustments in the middle of an at-bat.
He's got developing power and an excellent throwing arm in the outfield.
There's nothing not to like about what Myers brings to the table.
A.J. Pierzynski might not produce the career-high numbers that he did in 2012 for the White Sox (22 home runs, 77 RBI), but he's a solid hitter with pop and a major upgrade over Geovany Soto, both at the plate and behind it.
With a relatively inexperienced starting rotation, Pierzynski's game-calling ability will prove to be invaluable to the Rangers as they try to reclaim their spot atop the AL West.
R.A. Dickey, Jose Reyes or Josh Johnson would have been fine choices here as well, but the Toronto Blue Jays needed reliable starting pitching desperately, and they don't get much more reliable than Mark Buehrle.
For the past dozen years, Buehrle has taken the ball every fifth day and given his team a chance to win, pitching to a 3.81 ERA and 1.27 WHIP over that time.
He's notched 10-plus wins and 200-plus innings in each of those 12 seasons.
Denard Span, 28, is one of the more underrated outfielders—and leadoff hitters—in the game.
Capable of hitting .300 and an on-base machine—as evidenced by his .357 career on-base percentage—Span is a virtual lock to score 100 runs sitting atop the Nationals' potent lineup in 2013, thanks to his combination of base-running smarts and excellent speed.
Defensively, Span is a stud, even by advanced metrics. Via FanGraphs, Span posted a 9.6 UZR/150 and 20 DRS—numbers that are second only to free agent Michael Bourn, and Span costs a fraction of what Bourn will eventually sign for.