NL Rookie of the Year Rankings: Can Kirk Nieuwenhuis Challenge Bryce Harper?

With Bryce Harper taking over the top spot in last week's NL Rookie of the Year rankings, does that take all suspense out of the race? Is this going to be The Bryce Harper Show from now until October?

Well, maybe. Especially if Harper continues to play as well as he has. But if he slips up at any point, there are several rookies having impressive seasons who were ahead of him in our rankings for most of the season and could leapfrog him to front-runner status again.

Still among the honorable mentions are the Rockies' Jordan Pacheco, Randall Delgado of the Braves, the Brewers' Norichika Aoki and Harper's Nationals teammate, Steve Lombardozzi. Considering he was once looked like the favorite, the Padres' Yonder Alonso should be here too, but his batting average and OPS continue to plummet. 

While there's no change among our top five, each of the candidates had a strong week. Here are the five leading contenders for NL Rookie of the Year.

5. Wilin Rosario, Colorado Rockies

Last week: No. 5.

In a season that's fast becoming unbearable to watch for Colorado Rockies fans, rookie catcher Wilin Rosario has provided one of the few signs of encouragement.

Rosario leads all major league rookies with nine home runs and is tied for second among his peers with 27 RBI. His .758 OPS also ranks seventh among first-year players. 

The past week wasn't a great one for Rosario at the plate, as he batted 3-for-15 (.200) with two RBI. Those three hits were in his past two games, however, so maybe he's heating up a bit. 

Rosario definitely still needs some work with blocking pitches. No catcher has more passed balls than his nine, and that's despite catching almost 200 fewer innings than the elite backstops in the game. Rosario also has 17 wild pitches, tied for the third-highest total at his position. 

4. Wade Miley, Arizona Diamondbacks

Last week: No. 4.

In our previous rankings, Wade Miley stayed in the No. 4 spot despite having not yet pitched for the week. That gave him two starts in the subsequent seven days since our last list and the D-Backs' left-hander pitched well in both of them.

Throwing a combined 14.2 innings, Miley allowed two runs and 12 hits. As he's done all season, he showed excellent control, walking just one batter. But what stood out in those two starts were the 16 strikeouts Miley racked up. He struck out a season-high eight batters in each appearance. 

Miley didn't do this against milquetoast competition either. The first of those two starts was against the Texas Rangers, who have scored the most runs and have the highest run differential in baseball. Miley held the reigning two-time AL champs to one run and three hits over 7.2 innings. 

As Fox Sports Arizona's Jack Magruder writes, Miley seems to be getting better as the season progresses. If there was a rookie wall for him, it may have been at the end of May. But Miley appears to have pushed through it and is stronger for the effort. 

3. Zack Cozart, Cincinnati Reds

Last week: No. 3.

With six wins in their past seven games going into Tuesday's play, the Cincinnati Reds are beginning to pull away in the NL Central. A big factor in that is the explosion of Joey Votto, who's taking on that MVP look. But the Reds are also benefiting from major contributions from its role players.

Zack Cozart isn't a prototypical leadoff hitter, but he's probably the best man for the job on the Reds' roster. While it would be nice if he drew more walks at the top of the order, his 66 hits lead major league rookies. So he's hitting his way on base, giving Votto, Brandon Phillips and Jay Bruce someone to drive in. His .731 OPS is seventh among Reds hitters. 

Perhaps more importantly, Cozart is playing good defense at shortstop. According to Fangraphs, he's the third-best shortstop in the NL based on Ultimate Zone Rating. And his four Defensive Runs Saved are the second-highest total at his position. 

2. Kirk Nieuwenhuis, New York Mets

Last week: No. 2.

If the general baseball-watching populace didn't realize who Kirk Nieuwenhuis was, he probably got their attention last week. 

In his past six games, Nieuwenhuis hit 8-for-25 (.320) with three home runs and four RBI. Two of those homers came in a single game, last Thursday against the Tampa Bay Rays. Nieuwenhuis hadn't hit for much power all season, but his recent surge pushed him to six homers, tied for third among big league rookies. 

While Nieuwenhuis' numbers may not truly stand out, especially as hitters like Lucas Duda and Ike Davis begin to assert themselves, the rookie has been a consistent presence at the top of the order and in the outfield for Mets manager Terry Collins throughout the season.

As a result, Collins isn't thinking of benching Nieuwenhuis as veterans like Jason Bay return from injury. He's figuring out how to keep his rookie in the lineup. 

1. Bryce Harper, Washington Nationals

Last week: No. 1.

It's not inevitable that Bryce Harper will win the NL Rookie of the Year award, though many were ready to give him the honor as soon as the Washington Nationals called him up from Triple-A Syracuse.

But Harper has been everything the Nationals hoped for since joining the major league roster. He's brought energy and enthusiasm to the lineup, gotten on base, and provided excellent outfield defense. He's also drawn the majority of media attention, allowing the likes of Adam LaRoche and Ian Desmond to quietly go about their business.

However, Harper showed over the weekend that he's still not above being humbled. On Saturday against the New York Yankees, Harper went 0-for-7 with five strikeouts, a rather stunning performance considering how well he's played recently. Obviously, the rookie had never seen anything like Andy Pettitte's cutter before. 

But the Nationals had to be encouraged by how Harper rebounded from the setback. The 0-for-7 game was not the beginning of an extended slump. Harper came back the next day and hit 2-for-4 with a double. That kind of resilience is what sets him apart, even on his own team. 

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