NL Rookie of the Year Power Rankings: Hamilton losing grip on top spot

Every week until the end of the season, we'll take a look at the top first-year players in the National League and size up their candidacy for the Rookie of the Year.

Billy Hamilton may want to start heeding his own advice:

I can't stop now. This last month is big for me, I have to finish the season strong. I'm looking forward to this month.

So far, no good. Hamilton's poor monthly splits look even less flattering nearly two weeks into September, as the 24-year-old is struggling to a .143/.226/.143 slash line with no extra-base hits or steals.

Despite his underwhelming hitting rates, he's still leading rookies in most counting stats and, as pointed out in this space last week, his ability to suit up every day at a premium position bolsters his candidacy.

Finishing strong is key to Hamilton's continued development - not to mention his case for Rookie of the Year.

Jacob deGrom is making up for a late-season start in a big way, and a few more dominating outings could tip the Rookie of the Year race in his favor.

The right-hander's performance against Colorado this week was his best yet, tossing eight scoreless innings of three-hit ball with nine strikeouts. He threw 75 of his 100 pitches for strikes and lowered his ERA to 2.62 - a mark that would tie him for fourth in the NL, if qualified.

From ESPN's Mark Simon:

The Elias Sports Bureau notes that he’s one of three pitchers in Mets history to have an ERA below 3.00 through the first 20 starts of his debut season. The other two: Tom Seaver and Dwight Gooden.

The 26-year-old figures to make three more starts this season, likely coming at home against Miami, at Atlanta, and back in New York versus Houston.

The Diamondbacks outfielder could soon find himself out of the race and lineup with news he's set to undergo an MRI on his ailing back.

David Peralta's story - he ditched pitching after enduring multiple surgeries - is a good one, and here's hoping he finishes the season on the field.

New York Mets catcher Travis d'Arnaud is this week's high riser thanks to a red-hot stretch that has his second-half slash line up to .274/.318/.482.

The 2007 first-round pick has been even better in September - clubbing a homer and four doubles in eight games.

With other candidates either injured or slumping, d'Arnaud could make a surprise run into the top three before the year is out.

Kolten Wong has hits in 13 of his last 16 games, though he hasn't drawn a walk since Aug. 29. His on-base percentage sits at a meager .291 over the last 30 days, but defense like this will keep the Cardinals second baseman in the lineup: