Identifying Huge Liabilities on Every MLB Contender Entering Stretch Run

The 2012 Major League Baseball season ends on Oct. 3, leaving just about seven weeks between now and then for clubs to lock up postseason berths.

We have entered the stretch run, folks. Given the extra wild card in each league and the amount of division races that are still tight, it should be interesting.

None of MLB's contenders (there are 16 of them at the moment) are perfect. Each of them has certain areas of the game that they struggle with, and all of them have more talent in some places than they do in others.

Because the trade deadline is over and done with, and because it's hard to find significant upgrades via waiver deals, teams are pretty much stuck with what they have the rest of the way. That's all well and good for the most part, but here's a look at one player from each contender who is going to be a liability in the stretch run.

Note: All stats come from Baseball-Reference.com unless otherwise noted. We'll start in the AL East and progress towards the NL West.

New York Yankees: Russell Martin

There never used to be any easy outs on the Yankees. Nowadays, there's at least two on a daily basis.

One is Ichiro, who is only hitting .271 with a .301 OBP as a member of the Yankees. He's a lot better than Russell Martin, though, who is still hitting under .200 for the season with a .311 OBP.

According to FanGraphs, Martin's .306 weighted on-base average ties him with Jesus Montero for third-lowest among major league catchers with at least 300 plate appearances. The only catchers more offensively inept than Martin and Montero are John Buck and Kurt Suzuki.

To be fair to Martin, he's been better since the All-Star break, hitting .247/.341/.429 with four home runs in 24 games.

All four of those home runs came in July, however. In August, seven of Martin's nine hits have been singles.

It would be one thing if Martin was making up for his poor offense with good defense, but he's not. He has a minus-five DRS a year after posting a plus-seven DRS, and his caught-stealing percentage has gone down as well.

His catcher's ERA, meanwhile, has gone up from 3.70 in 2011 to 4.10 this year. 

Yankees fans should get a good look at Martin. Odds are these last few weeks will be his last in pinstripes.

Tampa Bay Rays: B.J. Upton

B.J. Upton is a perfect example of a hot-and-cold player. He'll be the most mediocre player under the sun for months at a time, and the next thing anybody knows he'll start playing like an All-Star.

That's kind of how Upton is playing now, as he has six home runs in 28 games since the break after hitting just seven home runs in 71 games before the break. He's slugged three home runs in Tampa Bay's last three games.

But here's the thing about Upton: Even when he gets hot, he's still pretty mediocre.

Upton may have six home runs and a decent .447 slugging percentage since the break, but he's only hitting .228 with a .294 OBP. His OBP in August is a mere .261.

Not exactly ideal seeing as how Upton has hit exclusively out of the No. 2 spot in the last few weeks.

Upton isn't having a great season in the field, either. He has a reputation of being an above-average defensive center fielder, but both his UZR and DRS are in the red this season, according to FanGraphs.

Upton deserves this much credit: When he's swinging the bat well, the Rays look unbeatable. The problem with him is that he's rarely swinging the bat well, and even when he is, he's still a player with a lot of flaws.

Baltimore Orioles: Mark Reynolds

Mark Reynolds is showing signs of life. He has an .845 OPS thus far in August, and he's already nearly matched his walk total from the entire month of July.

His old power is still nowhere to be seen, however. Reynolds hit only two home runs in July, and he has just one so far in August.

The O's have been waiting patiently all season for Reynolds' power to come along, and you really have to hand it to Buck Showalter for continuing to pencil Reynolds' name into his lineup on a daily basis. But for a variety of reasons, Reynolds just hasn't been able to drive the ball with any consistency this season.

The one thing he's still doing as well as ever before is striking out. His 31.2 strikeout percentage is right along the lines of his career average heading into this season.

Defensively, Reynolds has spent the majority of his time at first base for the first time in his career, and that's where he's going to stay now that Manny Machado has the hot corner on lockdown.

Reynolds is a better defensive player at first than he is at third, but it's not like he'll be winning a Gold Glove anytime soon. Per FanGraphs, both his UZR and DRS are in the red.

Reynolds isn't the worst first baseman in the league, but it's fair to ask how many other teams he would even be starting for if he wasn't on the Orioles.

Note: Left field also is a problem for the Orioles, but it's not a problem that can be pinned on any single player.

Chicago White Sox: Gordon Beckham

The White Sox are a team of inconsistent hitters, but the one guy who's been inconsistent all season is Gordon Beckham.

Beckham is hitting just .226/.279/.357 this season with 11 homers and 42 RBI. According to FanGraphs, his .277 weighted on-base average is tied for second-worst among qualified major league second basemen.

He's gotten even worse since the All-Star break. In 28 games, Beckham is hitting .173/.243/.286 with a pair of home runs and five RBI. He's shown signs of life in August, but a .626 OPS for the month hardly qualifies him as hot.

So we know that Beckham is an inferior hitter, and we certainly know that inferior hitters better play superior defense to justify being in the lineup day after day.

Beckham's not doing that. He's not a bad defensive player, but he doesn't qualify as a superior defensive player, either. His 0.4 UZR and minus-three DRS (per FanGraphs) make him, at best, a decent defensive second baseman.

Beckham's WAR for the season is 0.2. There's only one everyday second baseman with a lower WAR than that.

And we'll get to him in just a moment...

Detroit Tigers: Anibal Sanchez

The Tigers very much needed to make a deal for a starting pitcher at the trade deadline, and I'll freely admit that I had Anibal Sanchez pegged as a good pickup.

The only concern I had at the time was that Sanchez may not take to pitching in the American League all that well.

That fear has been realized in the four starts Sanchez has made for the Tigers. He has an ERA of 7.97 and a WHIP of 2.11 since coming over to Detroit, and opponents are hitting him at a .380 clip with a .598 slugging percentage.

The Tigers are a good offensive team, but asking them to pick up the slack for Sanchez is asking too much. The Tigers have lost three of his four starts.

The Tigers won't be able to stick with Sanchez for much longer if his struggles continue. They're already two games behind the White Sox in the division, and the White Sox have made it abundantly clear that they're not about to oblige everyone by finally running out of gas.

Sanchez was supposed to help the Tigers catch them, but he's been part of the problem instead of part of the solution.

Texas Rangers: Ryan Dempster

Speaking of trade acquisitions who haven't panned out, Ryan Dempster is in exactly the same boat as Anibal Sanchez.

As Danny Knobler of CBSSports.com pointed out, Dempster was not Plan A for the Rangers. They wanted guys such as Cole Hamels, Zack Greinke and Cliff Lee. Not Dempster.

They ended up having to settle for Dempster, and they had no choice but to hope that his stuff would work just as well in the American League as it did in the NL Central.

Nope. 

Dempster has an 8.31 ERA and 1.73 WHIP in three starts with the Rangers. Opponents are hitting .348 off him with an absurd .710 slugging percentage. In just 17.1 innings, he surrendered five home runs.

Texas' starting rotation is not better with Dempster in it. If anything, it's gotten worse. Getting him straightened out is without a doubt the club's top priority going forward.

And seeing as how they also have to worry about Yu Darvish's wildness and Derek Holland's gopheritis, that's saying something.

Oakland A's: Jemile Weeks

Even when the A's were lighting the world on fire in July, they were not a team without flaws. It's just that their flaws were easy to overlook as the wins kept piling up.

The A's have fallen back to earth. They're 5-6 in August, and only a handful of teams have scored fewer runs than they have.

Now their flaws are on full display, and that means it's once again easy to notice just how poor of a season Jemile Weeks is having.

After hitting .303 as a rookie, Weeks is hitting just .220/.304/.304 this season. According to FanGraphs, Weeks' .277 weighted on-base average ties him with Beckham for the second-worst among qualified major league second basemen. His 0.1 WAR is the worst mark among second basemen.

This is thanks to the fact that his poor offense has come packaged with poor defense. Weeks has a UZR of minus-3.6 and a DRS of minus-11.

He's not the worst player in baseball this season (Jeff Francoeur has my vote), but Weeks certainly is in the discussion.

Los Angeles Angels: The Entire Bullpen

Granted, we're singling out a group of players here rather than a single player. But in this case, an exception simply has to be made.

The Angels have as much collective talent as any team in the major leagues. They have baseball's best overall player in Mike Trout in their lineup, not to mention two elite sluggers in Albert Pujols and Mark Trumbo. Their starting rotation consists of a true ace in Jered Weaver and a handful of quality starters backing him up.

The only place the Angels are lacking talent is in their bullpen, and it just so happens their bullpen has been their Achilles heel in the month of August.

We're not even halfway through August, and Angels relievers already have lost five games while compiling an 8.37 ERA. They only have one reliever with an ERA under 4.32 for the month (Kevin Jepsen at 1.80).

The Angels can't get Scott Downs and Jordan Walden back soon enough, because right now Mike Scioscia may as well start picking fans out of the stands to come in and handle the late innings. It's that bad.

Washington Nationals: Bryce Harper

It's saying something about how good the Nationals are that their biggest liability at the moment is arguably the greatest 19-year-old hitter ever.

Or, at least, Bryce Harper used to be in that discussion. He's not so much anymore, as his production has been in a tailspin since the All-Star break.

In 30 games since the break, Harper is hitting .183/.273/.261 with just four extra-base hits and seven RBI. His .534 OPS since the break is by far the worst among Nationals regulars.

To be fair to Harper, he still does things to help the Nationals win. He's already one of the best in the league at creating runs on the basepaths, and he checks out as an above-average defensive outfielder, according to the advanced stats (see: FanGraphs).

But good baserunning and good defense are only worth so much when the hits aren't coming, and things are made all the more complicated by the possibility that calling up Harper so soon may not have been a good idea. 

Everyone is freaking out about Stephen Strasburg and his innings limit. What everyone should be freaking out about right now is Bryce Harper and his dreadful slump.

Atlanta Braves: Dan Uggla

The Atlanta Braves are doing just fine since the All-Star break. They're 20-10 in 30 games and have grabbed hold of the top wild card spot in the National League.

It's not all good, though. The Braves have to be wondering what they need to do to get Dan Uggla going again.

Uggla started off the season hot, posting an .831 OPS with eight homers and 31 RBI in the season's first two months. Since then, however, he's cooled down considerably. He's hitting .162 with a .597 OPS since June 1.

The All-Star break doesn't seem to have done Uggla any good. He's hitting just .187 thus far in the second half with a single home run and 13 RBI in 27 games.

The Braves won't need Uggla to snap out of his slump as long as they keep getting quality innings out of Ben Sheets, Paul Maholm and Mike Minor, but expecting those three to keep it up for much longer isn't a very good bet. A time will come when the Braves offense is going to have to pick up just as much slack as it did in the first half.

And that's when they're going to need Uggla to start hitting like he was in the first two months of the season.

Cincinnati Reds: Zack Cozart

The Reds are not unlike the Nationals in the sense that there's really not much to complain about where they're concerned. Their pitching has been excellent (and, just as important, healthy) all season, and they've managed to widen their lead in the NL Central in the second half despite not having the services of Joey Votto.

But the one problem area on the Reds that continues to stick out like a sore thumb is their lack of a leadoff hitter. To that end, one's eyes naturally shift toward poor Zack Cozart.

Cozart is a solid young player, but he's a guy who really has no business batting leadoff. He's been forced to bat leadoff this season simply because Dusty Baker doesn't have any better options and presumably because Cozart has assured him that he doesn't mind taking one for the team game after game.

Cozart has hit leadoff 82 times this season, yet he's hitting just .218/.260/.369 when he bats leadoff. Compare that to .357/.416/.571 when he bats second in the order.

The Reds' lack of a true leadoff hitter hasn't killed them this season, so it's doubtful that it's going to cost them a spot in the playoffs in the long run. And indeed, there are nice things to say about Cozart, as he's a very good fielder who still has room to grow as a player.

All that can be said is that the Reds would much rather go into the postseason with a steady leadoff hitter than without one. That means Baker either has to find someone else (not likely) or Cozart has to get better (also not likely).

Pittsburgh Pirates: James McDonald

James McDonald was Pittsburgh's best starting pitcher before the All-Star break. In 17 starts, he went 9-3 with a 2.73 ERA and a 0.97 WHIP.

The tables have turned. Since the break, McDonald has been Pittsburgh's worst starting pitcher.

He's made six starts since the break, and in those he has a record of 1-2 to go along with an 8.71 ERA and a 2.03 WHIP. Opponents have gone from hitting .196 against him to hitting .321 against him.

The Pirates are hoping that a little extra rest will cure what ails McDonald, as Rob Biertempfel of the Pittsburgh Tribune-Review has reported that McDonald's next start has been pushed back from Thursday to Friday.

If that doesn't work, the Pirates are going to be in trouble. They need McDonald to be a second ace alongside A.J. Burnett if they want to have a shot at catching the Reds in the Central.

It's also definitely worth mentioning that their hold on the NL's second wild card spot is hardly secure. To return to the postseason for the first time in two decades, they're going to need all hands on deck.

St. Louis Cardinals: Rafael Furcal

Rafael Furcal was a great story early on in the season, as he hit .333 with an .851 OPS in April and May. He had no trouble racking up All-Star votes.

Whoever voted for him voted too soon. Furcal went into a slump in June and has yet to climb out of it. He's hitting an even .200 with a .280 OBP in his last 56 games, and he has just a .545 OPS since the All-Star break.

To make matters worse, this hasn't been Furcal's best defensive season. Per FanGraphs, he has a UZR of minus-8.0 and a DRS of minus-three.

To make matters even worse, Furcal's back has been acting up recently. 

So what the Cardinals have at shortstop is a player who can't hit or field, and who's probably going to be limited by a creaky back for the rest of the season.

It's a good thing they're pitching and hitting so well right now, because it doesn't look like Furcal is going to be much help down the stretch.

Los Angeles Dodgers: Brandon League

Hanley Ramirez and Shane Victorino have been good enough since the Dodgers acquired them before the trade deadline. Their two big bullpen acquisitions, however, haven't panned out.

Randy Choate got knocked around in his first two appearances for the Dodgers, giving up three earned runs in just an inning's worth of work. 

He's since settled down, though, and his struggles frankly pale in comparison to Brandon League's struggles since the Dodgers picked him up.

League has made five appearances for the Dodgers, in which he surrendered five earned runs on seven hits and a walk in just 2.2 innings. His ERA with the Dodgers sits at 16.88.

Acquiring League allowed the Dodgers to trade Josh Lindblom to the Phillies for Victorino. That didn't seem like such a bad idea at the time, as surely an experienced setup man such as League would be able to step into Lindblom's shoes without any issues.

There have been issues, alright. And as long as League is struggling, the Dodgers basically are going to be forced to tough it out without a primary eighth-inning setup man.

Note: James Loney also stinks, but at least he's a very good defensive first baseman.

San Francisco Giants: Hunter Pence

The Giants gave up a lot to get Hunter Pence, but the trade was justifiable because of all the moves the Dodgers were making. The Giants simply were compelled to respond with a big move of their own.

Needless to say, they were hoping for more than what they've gotten out of Pence.

Outside of his big three-run homer against the Rockies on Sunday, Pence has been a big disappointment. He's hitting just .145 with a .445 OPS as a Giant, and he's struck out a total of 10 times in his last 25 at-bats.

Pence needs to hit because he's not much of a fielder anymore these days. Teams still have to watch out for his arm, but Pence's UZR is minus-4.2 and his DRS is minus-five, according to FanGraphs.

And indeed, playing right field at AT&T Park and playing right field at Citizens Bank Park are two vastly different challenges. AT&T Park is one of the toughest right fields in the majors.

The Giants have been scoring runs in bunches since the All-Star break, but their lineup won't really come together until Pence gets hot. 

Exactly when that's going to happen is anyone's guess and easily the Giants' biggest concern. 

Arizona Diamondbacks: Ian Kennedy

The Diamondbacks have been playing solid baseball since the All-Star break. They have a 3.68 team ERA, and only Washington and San Francisco have scored more runs than they have among NL teams.

One guy who continues to be a mystery, however, is Ian Kennedy.

Kennedy hasn't resembled the pitcher who won 21 games with a 2.88 ERA in 2011. He's been up and down the entire season, and right now he's about as unpredictable as any pitcher in the league. 

In his last three starts, Kennedy has surrendered 10 earned runs and six home runs in just 16.1 innings. To put that in perspective, he had allowed just six home runs over a span of 59 innings before his three most recent starts.

So it goes for Kennedy. It's pretty clear by now that he's just not the ace of Arizona's staff this season. And since he's clearly not the ace of the staff, exactly who is supposed to be the ace of the staff now is a matter of debate.

It's no wonder the Diamondbacks were apparently trying to trade for an ace ahead of the trade deadline. They must have known they were going to need one before long.

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