NL Rookie of the Year Rankings: Todd Frazier Rises, While Bryce Harper Slides

The past week wasn't a great one for most of the NL Rookie of the Year contenders we've included in our rankings. But we may be seeing some separation between the very top of the class and the other leading contenders for award honors. 

One rookie who had an impressive week but didn't climb back into the top five is San Diego Padres first baseman Yonder Alonso. Since last week's rankings, Alonso went 10-22 (.455) with five doubles, one home run and six RBI. But overall, his numbers fall short compared to his fellow rookies.

Another name that might come up in the comments is the Chicago Cubs' Anthony Rizzo. Rizzo was mentioned a couple of times last week. His numbers are undeniably impressive. For instance, he leads NL rookies with a .938 OPS. Yet, Rizzo has only played in 29 games, so many fewer than his peers. At what point should he qualify? Or, should he just be on this list already?

OK, with that out of the way, let's move on to the business at hand. These following five players are whom we see as the current top candidates for the NL Rookie of the Year award. 

Please leave your responses and suggestions in the comments. If you haven't noticed by now, they're definitely considered when putting these rankings together each week.

5. Bryce Harper, Washington Nationals

Last week: No. 2.

How far the favored have fallen. 

Judging from the comments for these rankings over the past few weeks, many think Bryce Harper is a product of hype and shouldn't be on this list at all.

I don't know if that's how the majority of fans feel, since comments can be something of a vocal minority. However, Harper isn't doing very much to challenge that perception these days.

The second half just hasn't gone very well for the Nats' prized outfielder. In 79 plate appearances, he's batted .171/.266/.257 with one homer and four RBI.

If Harper keeps hitting like that, he's not going to be on this list much longer. 

The lack of power is especially troubling, since that's what the Nationals were hoping to get from him when he was called up from the minors in late April. Yet, Harper has only three extra-base hits since the All-Star break. 

As The Washington Post's James Wagner writes, opposing pitchers have now developed "a book" on Harper. He's especially having trouble recently against left-handed pitching. 

At this point, Nats manager Davey Johnson should strongly consider moving Harper out of the lineup's No. 2 hole, maybe to the sixth or seventh spot. Perhaps, that will happen once Jayson Werth returns to the Nats' roster. 

4. Wilin Rosario, Colorado Rockies

Last week: No. 4.

Between an ankle injury and the Colorado Rockies wanting to work Ramon Hernandez back into the lineup, Wilin Rosario hasn't seen a whole lot of time recently. 

Whether it's due to lingering effects from the injury or a lack of regular at-bats, Rosario has slumped a bit.

He batted 1-for-13 (.077) with no home runs or RBI in the three games he's played since last week's rankings. 

Despite the missed games and slump that's come with it, Rosario still leads NL rookies with 16 homers and 40 RBI, while his .783 OPS ranks third among rookies who have played at least 60 games. (The Cubs' Anthony Rizzo has a .938 mark in 29 games.)

But when we talk about Rosario, we have to talk about his defense.

Though he's been putting in extra work with a catching instructor to improve his defense, as The Denver Post's Troy Renck writes, Rosario still leads major league catchers in wild pitches (12) and passed balls (31) allowed. The passed balls are six more than the next closest catcher—the Los Angeles Dodgers' A.J. Ellis.

3. Zack Cozart, Cincinnati Reds

Last week: No. 3.

The fact that the Cincinnati Reds were looking for a leadoff hitter like Shane Victorino or Juan Pierre leading up to Tuesday's trade deadline is an indication of how poorly Zack Cozart has been hitting lately. 

It's not entirely his fault, however. Cozart just isn't a leadoff hitter, yet manager Dusty Baker continues to put him at the top of his lineup because there's really no one else suited for the job. Plus, Cozart provides some pop with 10 home runs—the third-highest total among NL rookies.

(Drew Stubbs fits the classic profile of a leadoff hitter with speed, but he's been as bad—or worse—at getting on base than Cozart.) 

Despite Cozart's lack of success at the leadoff spot, the Reds just keep on winning. Cincinnati has won 15 of its 18 games since the All-Star break, reeling off a 10-game win streak during that span. 

Part of that is surely due to the defense Cozart provides at shortstop. Fangraphs' Ultimate Zone Rating currently rates him as the fifth-best defensive shortstop in baseball. That's what keeps him in the starting lineup every day, though, the Reds would surely like to see some improvement in his hitting. 

2. Todd Frazier, Cincinnati Reds

Last week: No. 5.

How have the Cincinnati Reds continued to win with their best hitter and MVP candidate Joey Votto sidelined after knee surgery? Getting excellent production from fill-ins like Todd Frazier has played a big role in that success.

At this point, referring to Frazier as a fill-in is marginalizing his contribution, so let's not do that. He's been a major contributor for the Reds this season.

His 12 home runs and 37 RBI are second among NL rookies behind Wilin Rosario. And among first-year players who have appeared in at least 60 games, Frazier has the highest OPS at .863.

However, Frazier has stepped in to help cover for major injuries.

With Scott Rolen out due to shoulder troubles, Frazier filled in more than capably at third base, giving Reds manager Dusty Baker a tough decision to mull over when Rolen was ready to return. But with Votto's injury, Frazier has substituted at first base and kept the team running smoothly.

He's been an extremely valuable asset for Baker this season and currently looks like the best rookie position player in the NL. 

1. Wade Miley, Arizona Diamondbacks

Last week: No. 1.

In his first of two starts, Wade Miley made since last week's rankings, the New York Mets roughed him up a bit. Pitching 5.1 innings, Miley allowed three runs and nine hits with only three strikeouts. 

But the Mets might just be a bad matchup for Miley.

In their previous meeting, the Mets tagged him for four runs and seven hits in six innings. 

Miley rebounded nicely in his next appearance, however. Facing the Dodgers, the left-hander allowed one run and three hits while striking out seven batters in eight innings of work. It was the third time this season that Miley had pitched that many innings. He worked efficiently, throwing 110 pitches. 

With that performance, Miley's ERA dropped to 2.98—the ninth-best mark among NL starting pitchers. His 1.08 WHIP (walks and hits per innings pitched) ranks him sixth in the league. 

Tuesday's start was the third time Miley pitched against the Dodgers this season, which might just demonstrate that he can have success when facing an opponent more than once.

Christian Cable brought up an interesting point in last week's comments, saying that rookie pitchers have an advantage because hitters have never seen him before. And perhaps, Miley was the beneficiary of that unfamiliarity. But with one team, at least, he's shown there's no book on him.

If the D-Backs' rotation stays on schedule, Miley could face several opponents for the second time during August and September. It could be worth keeping an eye on how he does against teams such as the Astros, Reds, Giants and Marlins. 

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