If you're an American League fan in the mood to see some good rookies in action, I recommend looking west.
The West Coast is home to the best rookie/player/New Jersey native on the planet in Los Angeles Angels outfielder Mike Trout, but he's not the only rookie doing work out west. The Texas Rangers have an excellent rookie of their own in Yu Darvish, and the Oakland A's have built their success this season largely on the backs of rookie players.
Yoenis Cespedes stands out as being the most impressive A's rookie, but most of Oakland's best rookies make their living on the mound. In fact, their starting rotation features four rookies at the moment, and they have several more rookies in their bullpen.
The A's and the AL West in general are very well represented in this week's AL Rookie of the Year rankings. Scroll ahead to see how the race is shaping up heading into the final two weeks of the regular season.
Note: All stats come from Baseball-Reference.com.
Scott Diamond, SP, Minnesota Twins
As recently as August 18, Diamond had an ERA under 3.00. In five starts ever since, he has an ERA over 7.00 and has been knocked around to the tune of a .315 opponents' batting average, one that comes complete with a slugging percentage of .583. Diamond could be out of the AL ROY picture altogether by the end of the season if he keeps this up.
Sean Doolittle, RP, Oakland A's
Doolittle isn't having a great month of September, but he still has a solid 3.35 ERA and he ranks second among AL rookie relievers in K/9 at 12.19. His 1.37 FIP is better than that of Aroldis Chapman, according to FanGraphs.
Kelvin Herrera, RP, Kansas City Royals
Herrera leads all AL rookies with 70 appearances this season, and he's sporting a 2.40 ERA and a solid 3.79 strikeout-to-walk ratio. He's just one part of a very exciting Royals bullpen.
Hisashi Iwakuma, SP, Seattle Mariners
A new addition to this week's list, Iwakuma finds himself in the ROY discussion because he's 5-4 with a 2.84 ERA since moving into Seattle's rotation in early July. With Felix Hernandez struggling, Iwakuma may be the best pitcher the Mariners have right now.
Will Middlebrooks, 3B, Boston Red Sox
Middlebrooks has been out of action for well over a month at this point, but his .288/.324/.509 triple-slash line, his 15 home runs and his 54 RBI in just 75 games make him at least worthy of an honorable mention.
Jesus Montero, C/DH, Seattle Mariners
Montero is hitting just .167 over his last seven games, and that's in no small way thanks to his 0-for-8 showing in Seattle's 18-inning loss to the Orioles on Tuesday night/Wednesday morning. Still, only Mike Trout has played in more games than Montero among AL rookies, and Montero's offensive numbers are badly skewed by his performance at Safeco Field. He's a .214/.257/.332 hitter at home and a .305/.337/.453 hitter on the road.
Robbie Ross, RP, Texas Rangers
Ross made his first appearance off the disabled list on Tuesday, and it went well. He pitched an inning against the Angels, allowing no hits or runs and striking out one. Garden-variety stuff for him. His 1.75 ERA leads all AL rookies.
Wei-Yin Chen, SP, Baltimore Orioles
Chen has allowed a total of four earned runs over his last 12.2 innings pitched, which equates to an ERA of 2.84. In other words, he's bounced back nicely from a six-start stretch that saw him compile an ERA of 6.55.
Chen is now 12-9 with an ERA of an even 4.00 this season. I'd say he's generally been the most consistent rookie starting pitcher in the American League this season, even if he's not the most spectacular hurler of the bunch.
Tommy Milone, SP, Oakland A's
Milone gets my vote as the most overlooked rookie in the American League. Only Yu Darvish has won more games among AL rookie pitchers, and only Chen and Matt Moore have started more games. Milone's ERA is 3.81, and he's put together a solid 3.41 ERA over his last six starts.
Matt Moore, SP, Tampa Bay Rays
Moore had a spot in my top five for several weeks, but he's out this week due to a rough stretch of starts thus far in September. In three outings, he's put together an ERA of 7.43 and has been knocked around to the tune of a .538 slugging percentage.
With an ERA of 3.88 and a K/9 of 8.98, I'd deem Moore's rookie season a success for the most part. He's skidding towards the finish line now, though.
Addison Reed, RP, Chicago White Sox
You never know what you're going to get from Reed when he's on the mound, but his 28 saves this season are tops among AL rookies by a mile. If his ERA wasn't an ugly 4.82, he'd be a lock for the top five.
Last Week: Unranked (on the cusp)
Ryan Cook's 2012 campaign is essentially a tale of three seasons.
In the beginning, it was good. Cook had a 1.34 ERA and was limiting opponents to a sparkly .107 batting average through his first 40 appearances in which he racked up nine saves and 11 holds.
In the middle, it was bad. In eight appearances between mid-July and early August, Cook put together a 10.13 ERA and got knocked around to the tune of a .361 opponents' batting average. In eight innings, he gave up four home runs.
These days, things are good again. In his last 14 appearances, Cook has gone retro, compiling a 1.26 ERA and a .184 opponents' batting average. He's allowed zero home runs and struck out 18 in 14.1 innings of work.
For the season, Cook now has a 2.44 ERA in 62 appearances with six wins, 14 saves and 16 holds.
Cook's ERA does not top the rookie charts, nor do his number of appearances. Kelvin Herrera has appeared in more games than Cook, and Robbie Ross' ERA is head-and-shoulders better than Cook's.
Cook is in the top five over both of them anyway because neither Herrera nor Ross has been as versatile as Cook has this season. Cook has just as many wins as Ross, and he ranks second among AL rookies in both saves and holds.
In fact, no pitcher in baseball has as many as six wins, 14 saves and 16 holds. Cook stands alone.
Last Week: No. 4
With Bartolo Colon suspended and Brandon McCarthy out for the foreseeable future as he recovers from a skull fracture, the A's have needed as much help as possible from their rookie pitchers in the month of September.
None of them has answered the call quite like Jarrod Parker. He's been Oakland's best starting pitcher in the month of September, which is saying something seeing as how A's starters have a collective 3.41 ERA this month.
Parker has logged seven innings in each of this three starts this month, allowing a total of five earned runs for an ERA of 2.14. He's struck out 12 and issued just three walks in 21 innings.
Parker has won his last two starts to push his record to 11-8 this season, and he has his ERA down to 3.51 and his WHIP down to 1.28. His FIP, according to FanGraphs, is 3.48.
A FIP such as that puts Parker in elite company. Only six starting pitchers in the AL have lower FIPs than Parker. The list of pitchers he ranks ahead of in that category includes names like CC Sabathia, James Shields, Jake Peavy and Jered Weaver.
FanGraphs has Parker's WAR at 3.2, second only to Yu Darvish among AL rookie starting pitchers.
Trevor Cahill, meanwhile, has a WAR of 2.9. Just sayin'.
Last Week: No. 3
Between August 19 and September 10, Yoenis Cespedes went 21 games without hitting a home run. In that span, he hit just .221/.253/.302 with six RBI.
Last week, Cespedes launched three home runs and drove in five runs in just six games, hitting a cool .389/.542/.944.
That's the kind of season it's been for Cespedes. He's either hitting missiles all over the yard, or he's doing his level best to be totally invisible.
On the whole, though, Cespedes' rookie season has been a good one. Nobody expected him to hit .291/.355/.491 in his first full season, and I'd say even his home run and RBI numbers are better than expected. Among rookies, only Mike Trout has more homers and RBI than Cespedes' 19 homers and 72 RBI.
FanGraphs has Cespedes' weighted on-base average at .366. You may be surprised to hear that that wOBA ranks him ahead of standout AL hitters such as Alex Rios, Albert Pujols, Adam Jones and even Derek Jeter.
So very quietly, Cespedes has actually been one of the top offensive producers in the AL this season. He's not on the same level as Mike Trout and Miguel Cabrera, mind you, but he's certainly giving the A's excellent value for the money they're paying him.
That sound you hear is Billy Beane breathing a sigh of relief.
Last Week: No. 2
There seems to be no stopping the roll that Yu Darvish is on, and that's a scary thought for the rest of the American League.
In his last six starts, Darvish is 4-1 with a 2.32 ERA. He's held hitters to a .151 batting average and has struck out 51 in 42.2 innings.
Darvish's last five starts have been particularly encouraging because he's walked only eight hitters in 36 innings of work. That equates to a BB/9 of an even 2.00.
In his first 22 starts, Darvish put together a BB/9 of 5.07, a number that presumably had Rangers pitching coach Mike Maddux in tears every night.
It's all water under the bridge now. Darvish is on fire, and his hot streak has put a nice shine on his numbers for the season. He now has a record of 15-9 and an ERA of 4.02. He ranks second in the American League behind Max Scherzer with a K/9 of 10.44, and FanGraphs has Darvish's FIP at 3.38.
That's good for sixth among AL hurlers, and it's a big reason why Darvish ranks fourth among AL starting pitchers with a WAR of 4.5.
Yeah, it's safe to say that Darvish's first season in the majors is already a big success.
Last Week and Every Week: No. 1
Time for all of us to come together for the weekly worship of Mike Trout.
Trout isn't having such a great month of September, as he's hitting just .274/.375/.403 with two homers and three RBI. He hasn't helped himself by posting back-to-back 0-fers to open the week.
Trout, however, is living proof of the notion that a walk is just as good as a hit in most cases. For example, he walked twice in Tuesday night's game against the Rangers and ended up turning both of those walks into runs.
That's what Trout does, and Dave Cameron of FanGraphs pointed out on Wednesday that Trout does it better than you probably realize:
Mike Trout has scored 45% of the time he's been on base.League average is 31%, Miguel Cabrera is at 28%.— David Cameron (@DCameronFG) September 19, 2012
A word to the wise: Don't put Mike Trout on base. If you do, he will score.
Trout is now looking up at Miguel Cabrera in the AL batting race, but his .327/.396/.558 triple-slash line is still absurdly good for a rookie. And though he and Cabrera are tied for the major league lead in wOBA at .420, according to FanGraphs, Trout still has a comfortable lead over everyone with a WAR of 9.4.
Cabrera's the better hitter, but there's no question Trout is the better player.
Oh, and yes, he is the best rookie in baseball. By, like, a hundred miles.
5. Matt Moore, SP, Tampa Bay Rays
Down and out this week. Possibly for good.
4. Jarrod Parker, SP, Oakland A's
Steady as she goes.
3. Yoenis Cespedes, OF, Oakland A's
2. Yu Darvish, SP, Texas Rangers
1. Mike Trout, OF, Los Angeles Angels
The Rookie of the Year award has been Trout's to lose for about four months.
Feel free to check out last week's rankings.
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