We probably spend way too much discussing and arguing about awards, but it's fun and fans like to argue about these things, so straight to the numbers. There are, I'd suggest, five reasonable Cy Young candidates in the American League:
Pitcher W-L ERA R/9 IP H BB SO HR OPS FIP Felix GS bWAR fWAR
Felix 14-5 2.14 2.47 219.0 160 41 225 15 .551 2.59 20 65.5 6.8 5.8
Kluber 16-9 2.54 2.87 219.2 195 48 244 14 .631 2.47 17 61.7 6.3 6.5
Sale 12-3 1.99 2.31 163.0 116 34 192 11 .543 2.46 11 66.4 6.5 5.3
Lester 15-10 2.45 3.06 205.2 181 46 206 15 .633 2.81 13 60.8 4.3 5.7
Scherzer 16-5 3.26 3.34 207.1 184 58 237 18 .661 2.88 12 59.3 5.6 5.2
(Some of the numbers above: OPS is OPS allowed; FIP is Fielding Independent Pitching; Felix -- named in honor of Felix Hernandez -- is the number of starts a pitcher had where he went at least seven innings and allowed two runs or fewer; GS is average Game Score; and bWAR and fWAR are from Baseball-Reference and FanGraphs.)
A few weeks ago, Hernandez appeared to be a Cy Young lock, with that stretch of 17 Felixes in a row, an all-time record. Over his last six starts, however, he has just one win and a 3.03 ERA. OK, that's not bad when your bad stretch still produces a lower ERA than Max Scherzer has on the season. Hernandez's main culprit in this period has been the home run: After allowing seven in his first 25 starts, he's allowed eight in those six, including four in one game to the Nationals.
Still, this little slump has allowed others to jump into the race. Corey Kluber had another outstanding effort on Tuesday, striking out a career-high 14 to earn his 16th win and lower his ERA to 2.54. He has a 1.84 ERA since the All-Star break and his FanGraphs WAR has also edged ahead of Hernandez's. While Hernandez's changeup is regarded with awe, it's time to view Kluber's curve with same level of appreciation, as opponents are hitting .094 against it in 198 plate appearances with no home runs and 113 strikeouts.
Chris Sale leads the AL with a 1.99 ERA, despite pitching in a tougher park for pitchers than Hernandez. He's closing in on Hernandez in both bWAR and fWAR and starts Wednesday against the Royals. The Condor's slider is reminiscent of another tall, slim lefty: Randy Johnson. Opponents are hitting .135 off it with just four extra-base hits (two home runs).
Jon Lester is close behind in ERA, innings and WAR, but he's also allowed 14 unearned runs, so his actual runs allowed per nine is significantly higher than Hernandez's. Scherzer's ERA is higher but he has solid peripherals; keep in mind that his ERA was hurt by that 10-run outing to the Royals -- all earned runs.
One category I like to look at is dominant performances. That's why I like the "Felix" -- if you go seven and allow two runs or fewer, you should win, or you've at least put your team in position to win. It's a better quick-and-dirty method than quality starts (six innings, three runs or fewer), which don't work as well in this era of depressed offense.
As you can see, Lester and Scherzer trail Hernandez significantly in that area. They've been terrific, but I feel comfortable knocking them off the list.
The problem I have in giving Sale the edge over Hernandez is that large gap in innings -- Hernandez has pitched 56 more innings. So why is Sale so close in WAR? The quality of opposition has been about the same (4.35 runs scored per game on average for Hernandez's opponents, 4.28 for Sale's), so it's all about park effects. But Felix has a 2.16 ERA at home and 2.11 on the road. This isn't a Sandy Koufax type of situation, where Hernandez derives an obvious and large benefit from Safeco Field. Maybe Sale has been slightly better on a per-inning basis, but I can't get over that gap in innings and the benefit has created in resting the bullpen.
That leaves Kluber. He's got the innings, the strikeouts and more wins than Felix. He's faced an easier group of opponents -- 4.09 runs on average -- and his runs per nine innings is still 0.40 higher than Felix's. That's a minor knock against him.
It could come down to wins, especially if Kluber gets up to 18 by the end of the season and Felix remains stuck at 14 or 15. But we probably all know the tough luck Felix has pitched in this year. Hernandez has seven games where's he allowed no runs or zero runs, tied for most in the majors (with Jeff Samardzija and Hector Santiago). Sale has six such games and Kluber four. If we increase the runs allowed to two, Hernandez has had 11 such starts where he didn't get the win, compared to eight for Sale and seven for Kluber.
I still think Felix is the guy. But it's close enough that these final two starts for each pitcher could make a difference.