The two Rookie of the Year races couldn't be more different right now. In the National League, Braves closer Craig Kimbrel has not only had the top spot on lock for most of the season, but he has been increasing his lead steadily over the last two months. In the American League, however, a quartet of bad starts by the Mariners' Michael Pineda has thrown the race wide open such that any of the five players below could win with the award with a strong finish.
Kimbrel is not just leading the majors in saves and five saves away from breaking Neftali Feliz's one-year old rookie record, he's putting together one of the most dominant relief seasons in the game's history. Only four relievers have had 50 or more innings pitched and an ERA+ above 200 and a K/9 above 14.0 in a single season: Eric Gagne in his Cy Young-winning 2003, Billy Wagner and Armando Benitez in 1999, and Brad Lidge in 2004. Kimbrel (203 ERA+) would be the fifth if he can sustain his current rates.
That might sound unlikely, but he has been untouchable for two solid months now. In 27 appearances since June 14, Kimbrel hasn't blown a save, taken a loss, or allowed a run. Over that span, he has allowed just 16 baserunners in 25 2/3 innings while striking out 41. He hasn't allowed an inherited runner to score all season (though he's only had four), and has allowed just one home run in 82 2/3 major league innings, including last year's postseason (hats off to the Reds' Ramon Hernandez, who went deep off Kimbrel on May 27). Kimbrel is also one shy of the record (since 1919, which is as far back as the gamelogs go) for the most scoreless relief outings by a right-hander in which no inherited runners scored, either. The two pitchers to get to 28? Some guys named Mariano Rivera (in 1999) and Joe Nathan (in 2004).
After going 0-for-6 to start July, Freeman was hitting .267/.336/.425 on the season, a poor showing for a first-basemen, rookie or otherwise (see: Hosmer, Eric). Since then, he has hit .349/.408/.562 with seven of his 16 home runs and 24 of his 58 RBIs in just 158 plate appearances and a 20-game hitting streak mixed in. However, he has cooled off significantly of late, with three 0-fers in his last six starts and just one home run in his last 96 plate appearances. Still, on the season as a whole, he has been the most productive rookie hitter in either league, leading all rookies with at least 200 plate appearances in batting average and on-base percentage and trailing only the Angels' Mark Trumbo and the Blue Jays' Eric Thames in slugging, and both by less than 10 points. He also leads major league rookies in hits, walks, doubles, and runs (tied with Danny Espinosa).
Espinosa has gone from hero to zero over the last month, hitting .146/.219/.198 without a single home run, RBI, or stolen base in 24 games and 106 plate appearances dating back to July 18. Still, he banked enough of those three counting stats prior to his current skid, and has played a strong enough second base, to hold on to his position here, at least for the time being.
Worley had a tremendous seven-start run following his mid-June recall from Triple-A, going 5-0 with a 1.14 ERA over that stretch and capping it off with a complete-game victory over the defending world champion Giants, but he also had tremendous luck during that run, as evidenced by a .177 opponents' batting average on balls in play. His last three starts have been one good (against the Giants again), one bad (against the lowly Dodgers), and one in the middle (against the nose-diving Pirates), adding up to a 6.35 ERA and reason to suspect he may not stick on this list, though he should stick as the fifth man in the Phillies' celebrated rotation.
The Braves' Brandon Beachy and the Diamondbacks' Josh Collmenter have both out-pitched Gee this season in similar playing time. However, despite the Cy Young votes of the last two years that made it clear a pitcher's won-loss record is no longer the overriding statistic in awards voting that it used to be, I suspect that unless one of those two can put a shine on his record over the final month and a half of the season (Beachy is 5-2, Collmenter 7-7), Gee will outpoll them in the Rookie of the Year voting. That is, unless Gee torpedoes his candidacy on his own. He is 3-4 with a 5.61 ERA over his last nine starts.
Pineda, who has a better WHIP, strikeout rate and walk rate than Hellickson, has clearly been the better pitcher this season, but Hellickson holds the advantage in wins and ERA, which could be enough swing the voters over to his side. Don't count out Pineda just yet, however. He rebounded nicely from a rough patch in mid-July to post a pair of quality starts in his last two outings, striking out 10 of Hellickson's teammates in the first of those. Further complicating things is the fact that the Mariners are starting to look for ways to limit Pineda's innings, and actually skipped him in the rotation between those two starts. He has never thrown 140 innings in a season and is currently at 136. Hellickson's career high was 155 2/3 frames last year. He's at 134 1/3 heading into this week's action.
On the surface, Walden seems to be enjoying a strong season as a rookie closer, but he blew his eighth save on Sunday, putting his conversion rate at 76 percent on the season. That's the second-worst among the 24 relievers with 20 or more saves this season (Joakim Soria is at 75 percent).
Trumbo leads major league rookies in home runs, RBIs, and slugging percentage (minimum 200 plate appearances), but his on-base percentage undermines all of that. In 422 plate appearances this season, Trumbo has drawn just 14 unintentional walks. Removing the six PA in which he was intentionally passed, that's one walk every 29.7 PA, an absolutely dreadful rate (the major league average is 13.3 UIBB/PA). Similarly, a high out-rate (which is what a low-OBP really is) is enough to keep Blue Jays catcher J.P. Arencibia's 19 homers and 53 RBIs off this list entirely. It should be noted, though, that Arencibia has drawn unintentional walks twice as often as Trumbo; he just can't buy a single, resulting in a .209/.272/.439 season line.
Nova leads major league rookies in wins and, after correcting for their disparate home ballparks, actually has a better ERA+ Pineda, which suggests that I'm undervaluing his candidacy a bit here. Nova has been coming on strong of late, too, going 7-0 with a 3.10 ERA and a solid 6.5 K/9 in his last eight starts. The catch is that the Yankees actually sent him to Triple-A for most of July, something his performance did not warrant, but A.J. Burnett's contract did. The "last three weeks" line above includes all three of his starts since his return, which saw Nova called up to make a spot-start in a doubleheader and immediately pitch his way into a permanent spot in the Yankees rotation. Included in those three starts is a game against the White Sox in which Nova struck out a career-high 10 while walking none and allowing just one run in 7 2/3 innings. Also worth noting: Nova, now 24, threw 187 innings between Triple-A and the majors last year and thus shouldn't be inhibited by innings limits down the stretch the way Hellickson and Pineda likely will.