NL Rookie of the Year Rankings: Yonder Alonso Swings His Way Back

We've passed the midway point of the baseball season and if an award was given out for Midseason National League Rookie of the Year, Bryce Harper of the Washington Nationals would have won the honors. 

However, the Rookie of the Year race won't be a runaway vote for Harper. Or at least it shouldn't be. The Arizona Diamondbacks' Wade Miley emerged as one of the best pitchers in the NL and should earn strong consideration for the award. 

But in the two weeks since we last posted our rankings, most of the top NL rookie candidates have struggled. Perhaps they needed the All-Star break more than anyone, playing through their first full major league seasons. 

Falling off the list after looking like a favorite for most of the season is New York Mets outfielder Kirk Nieuwenhuis. Not only was he continuing to struggle and see fewer at-bats while sitting against left-handed pitching, but Nieuwenhuis missed time due to a hand injury.

Milwaukee Brewers outfielder Norichika Aoki is also playing his way into honorable mention status. But I'm going to admit a bias here. I have trouble thinking of Aoki as a rookie when he played eight professional seasons in Japan. Maybe it shouldn't be different than if an American player spent eight years in the minors. That's a discussion worth having, if you're interested.

With that, let's get to this week's rankings. Going into the second half, here are the five leading contenders for the NL Rookie of the Year award.

5. Yonder Alonso, San Diego Padres

Last week: Unranked.

Returning to our rankings after being absent for a few weeks is San Diego Padres first baseman Yonder Alonso. Alonso looked like the favorite for NL Rookie of the Year honors at one point, but an awful June in which he hit .218 with a .545 OPS knocked him out of consideration. 

Alonso kept on swinging, however, and fought his way out of that June slump. So far in July, he's batting .282/.417/.436. In the two weeks since our last set of rankings, Alonso batted 13-for-36 (.361) with four doubles, two home runs and eight RBI. 

That surged has pushed Alonso's season average up to .266/.350/.373. His .723 OPS trails several fellow NL rookies, but Alonso does have 308 at-bats, more than any other rookie except Cincinnati Reds shortstop Zack Cozart. So he's arguably had more room to fail thus far. 

Alonso isn't the Padres' best offensive player right now, as he once appeared to be. That status goes to third baseman Chase Headley. 

However, Alonso is tied for the team lead in batting average and doubles. He looks capable of once again being an offensive leader if and when Headley and Carlos Quentin are traded to playoff contenders. 

4. Wilin Rosario, Colorado Rockies

Last week: No. 4.

Holding steady in our fourth spot is the Colorado Rockies catcher, who's lost a little bit of playing time to veteran Ramon Hernandez since the All-Star break. However, that's not an indication of Wilin Rosario's play so much as the Rockies' desire to showcase Hernandez for a possible trade.

Reports are that the Rockies are somewhat hesitant to deal Hernandez away because they feel he can be a mentor to Rosario, especially when it comes to calling pitches and blocking balls behind the plate. Those are the weaknesses in Rosario's game right now. His 27 wild pitches and 12 passed balls put him among the league leaders in those categories.

Rosario is making up for that with his bat, however. In seven games since our last set of rankings, he's batted 6-for-21 (.286) with a home run and three RBI. 

With 15 home runs, Rosario leads all major league rookies and his 39 RBI are tops among NL first-year players. Only three other NL rookies have a better OPS than Rosario's .826, and he has more plate appearances than the players ahead of him.

3. Zack Cozart, Cincinnati Reds

Last week: No. 3.

Cincinnati Reds manager Dusty Baker probably gave his rookie shortstop a break by taking him out of the lineup's leadoff spot. Zack Cozart showed some pop at the top of the order, but just wasn't getting on base as much as a leadoff hitter should. 

(The Reds' new leadoff hitter, Drew Stubbs, isn't exactly an on-base machine, either. But Baker thinks his speed makes him better suited for the top of the lineup.) 

July hasn't been good to Cozart thus far. He's compiled a .204/.268/.306 slash average so far this month, putting him on pace for his worst month of this season. In 11 games since we last posted NL Rookie of the Year rankings, he's batted 8-for-42 (.191) with one home run and three RBI. 

Cozart does lead all NL rookies with 84 hits, but it's worth noting that his 370 plate appearances are the most among his first-year peers. 

More importantly, Cozart is giving the Reds good defense at shortstop. Fangraphs ranks him as the sixth-best shortstop in the NL based on Ultimate Zone Rating. 

2. Wade Miley, Arizona Diamondbacks

Last week: No. 2.

After four consecutive starts in which he allowed just one run, Wade Miley not only looked like a Rookie of the Year candidate in the National League, but also a contender for the Cy Young Award.

If there was one player putting himself in position to challenge Bryce Harper for postseason honors, it was the Arizona Diamondbacks' left-hander. He was the D-Backs' lone All-Star representative. 

Miley hasn't performed as well in his past three starts, however. He's allowed eight hits in each of those appearances, giving up five homers and 15 runs. That's increased his ERA to 3.13, ranking him 14th among NL starting pitchers. Previously, he'd been in the top five. 

For a pitcher that pounds the strike zone as much as Miley does, he's bound to get hit. But it has to be a concern for the D-Backs that Miley is allowing as many hits as he has in recent starts. One of those eight-hit games was against the Los Angeles Dodgers, who weren't doing much hitting at all until Matt Kemp and Andre Ethier returned to their lineup.

The D-Backs are on the fringes of the NL West race now, seven games behind the first-place San Francisco Giants. A big reason for Arizona's slide down the standings has been its starting pitching. However, Miley has exceeded expectations, leading the team in wins and ERA. That gives the D-Backs something promising to build on. 

1. Bryce Harper, Washington Nationals

Last week: No. 1.

Is Bryce Harper largely a product of hype? Every week we post these NL Rookie of the Year rankings with him as the front-runner for the award, someone inevitably leaves a comment that Harper just gets more attention than any other first-year player. 

Has any other rookie made more of an impact on his team, however? When the Washington Nationals called Harper up at the end of April, their offense was on life support. They were wrestling for first place in the NL East on the strength of outstanding pitching. 

Harper may not be hitting for as much power as the Nats were hoping for when they promoted him from Triple-A Syracuse. But he's been a catalyst at the top of the batting order ever since manager Davey Johnson put him in the No. 2 spot. 

In the two weeks since we last posted these rankings, Harper has hit 13-for-46 (.282) in 11 games with three doubles and four RBI. His .804 OPS ranks third among the Nationals' regular hitters. That mark also puts him fifth among NL rookies. 

Should Harper have been named to the NL All-Star team? Probably not. That's an example where hype trumped actual achievement, and MLB ceded to Harper's popularity. 

Look at the Nationals' 5-4 walk-off win on Tuesday night, though. Harper drove in the game-tying run with a 10th-inning triple. He's come through with big hits when needed. He's made a difference. Would the Nats be in first place without him? 

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