NL Rookie of the Year Rankings: Bryce Harper Takes the Top Spot

Bryce Harper was a popular NL Rookie of the Year candidate going into this season, even if it was generally expected that he would begin the season in the minors. 

This week, inevitability has become reality. The continued decline of San Diego Padres first baseman Yonder Alonso (.259 average, .685 OPS) has knocked him off our rankings, moving everyone up a spot and creating an opening for a new contender.

There are plenty of good rookies to choose from, many of whom you've suggested in the comments over the past few weeks. The Rockies' Jordan Pacheco, the Nationals' Steve Lombardozzi, the Braves' Randall Delgado and the Brewers' Norichika Aoki all warrant honorable mentions for their numbers thus far. 

Each of those names could find their way into these rankings in the weeks to come. But this week, the following five players look like the top-five contenders for NL Rookie of the Year. 

5. Wilin Rosario, Colorado Rockies

Making his debut in our NL Rookie of the Year rankings is a player that's been getting a lot of support among commenters and e-mailers over the past few weeks.

Colorado Rockies catcher Wilin Rosario leads all MLB rookies in home runs with nine, and his 25 RBI are the most among NL rookies. So he definitely warrants a place on this list. Not including him before may have been an oversight, but it also indicated just how deep with quality this NL rookie class is.

Rosario should probably get extra credit for playing the sport's most difficult defensive position. Catchers' defense is a bit more difficult to rate than other positions, but Rosario is handling himself well behind the plate. He's thrown out a respectable nine of 20 base stealers. However, with seven passed balls allowed and 14 wild pitches, Rosario has some work to do with his blocking.

Those wild pitches aren't all on Rosario, of course. He's had to deal with a young pitching staff in Colorado, one that hasn't developed as well or quickly as the Rockies were hoping. That's another reason Rosario should draw heavy consideration in NL Rookie of the Year balloting. 

4. Wade Miley, Arizona Diamondbacks

Last week: No. 5

Wade Miley is scheduled to pitch Wednesday against the Texas Rangers, so he hasn't made an appearance since our rankings last week. It didn't seem fair to eliminate him in inactivity, and thus did nothing to warrant a move out of the top five.

And with Yonder Alonso sliding off the list of contenders, everyone else got an opportunity to move up a spot. That includes Miley, obviously.

Miley's last start certainly left a good impression, holding a strong Rockies lineup to one run and three hits over eight innings. Most importantly, he didn't walk anyone. That's been a key reason for his success this season. Miley is averaging 2.1 walks per nine innings.

With seven wins and a 2.53 ERA, Miley leads the Arizona Diamondbacks' starting rotation in each of those categories. As you might expect, that also means he leads all NL rookies in those statistics as well. 

The D-Backs may soon have a decision to make, attempting to figure out who might have to get squeezed out of the starting rotation if phenom Trevor Bauer gets called up from Triple-A  Reno. But one guy who doesn't have to worry about losing his job is Miley. 

3. Zack Cozart, Cincinnati Reds

Last week: No. 3

The Cincinnati Reds have been up and down over the past couple of weeks, losing seven of their past 12 games and are now just a game up on the surprising Pittsburgh Pirates in the NL Central through 60 games.

But the Reds haven't been slumping because of Zack Cozart. While not a classic leadoff hitter, he's giving the team production at the top of the order. Since last week's rankings, Cozart has batted 5-for-18 (.278) and drawn a couple of walks. That's pushed his OPS back up to .718, ranking sixth among Reds batters.

Cozart also deserves praise for his defense at shortstop. According to Fangraphs, he rates as the seventh best among NL shortstops in Ultimate Zone Rating, and his four Defensive Runs Saved are the second-highest total at SS. 

A national TV audience on ESPN's Sunday Night Baseball got to see how good Cozart can be, as he crushed a home run off the Detroit Tigers' Drew Smyly to lead off the third inning. Few teams get that kind of power from shortstop, which provides a nice luxury for the Reds.

2. Kirk Nieuwenhuis, New York Mets

Last week: No.1

It was a brief stay at the top of our NL Rookie of the Year rankings for Kirk Nieuwenhuis. The New York Mets outfielder got the nod last week because he'd been in the majors since the beginning of the season.

Nieuwenhuis has been a mainstay in the Mets outfield, giving manager Terry Collins someone who can reliably play every outfield position and hit consistently near the top of the batting order. As players like Andres Torres and Jason Bay have returned from injury, demoting Nieuwenhuis back to Triple-A Buffalo has never come up in discussion. The Mets need him too badly in the lineup.

The past week wasn't a great one for Nieuwenhuis, as he batted 2-for-13 (.154). Maybe facing the New York Yankees in interleague play for his first Subway Series got to him just a bit. (The Yankees pitching likely had something to do with that.) 

Nieuwenhuis also showed some courage by riding the 4 train to Yankee Stadium in full uniform before last weekend's series versus the Yankees. Sure, the whole thing was staged by MLB Fan Cave, but no other Met dared face hostile Yankees fans in an enclosed container. 

It was yet another example of the rookie showing he belongs in The Show.

1. Bryce Harper, Washington Nationals

Last week: No. 2

Was it only a matter of time before Bryce Harper ascended to front-runner status in the competition for NL Rookie of the Year?

Detractors think the Washington Nationals outfielder receives far too much hype over his fellow rookies. But he is undoubtedly an impact player and is making significant contributions to a first-place team that has the second-best record in the majors going into Tuesday night's play. 

How would Harper handle playing at Fenway Park for the first time with the Nats playing the Boston Red Sox in interleague play? As he's shown throughout his 39 games this season, nothing seems to faze the kid. Harper went 3-for-5 with a home run and three RBIs, introducing himself resoundingly to Red Sox Nation.

Rather than getting overwhelmed by the setting, Harper acts like he belongs, like he expects to be there. Some perceive that as cockiness, but for Harper, it seems to give him a strong sense of purpose. 

Harper leads all NL rookies in on-base percentage, slugging percentage and OPS, and his .295 batting average is behind only Norichika Aoki's .300 mark with Milwaukee. Personally, I think players like Nieuwenhuis should get more consideration for playing in more games than Harper has.

But that sort of thing is also dictated by circumstances. For instance, if the Nats didn't have a crying need for offense, would they have left Harper in the minors a bit longer? If Andres Torres hadn't gotten hurt, would Nieuwenhuis have been called up so early? 

Harper may not quite be the best hitter in the Nationals lineup yet, but he's certainly close. Without him, Davey Johnson and the Nats may not be in first place right now. How much bigger an impact can a rookie possibly have?

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