Raising Aces: Two Trains: Chris Sale and Patrick Corbin

Our first foray in the train station came last week, as we dug into the disparate cases of pitchers Johnny Cueto and Rich Hill. We have another veteran stud who has lost his way on the docket this week as we examine what is happening with Chris Sale, who has been uncharacteristically hittable in his last four starts, and the resurrection of Patrick Corbin, tackling a pair of southpaws who are riding in opposite directions on the performance rollercoaster.

Chris Sale

The last four starts for Sale have come against two different teams, covering home-and-home series with the division-rival Twins and Indians. Through the four-game stretch, the dominant Sale has a 5.40 ERA that seems only somewhat high until one realizes that six of the 20 runs that he has given up are unearned, resulting in a mark of 7.71 runs allowed per nine innings. All four starts have been disappointing in their own way, but the shape of his misery has morphed based on the identity of his opponent.

Game Stats vs. Cleveland

Date	IP	R	H	HR	BB	K	PC
Sep 18	7.0	7	8	2	3	9	116
Sep 7	7.0	3	7	3	1	8	108

The Indians have leaned on the longball to beat Sale twice in the past couple of weeks, mashing five homers through 14 innings against the Condor. Those bombs represent one-third of the total hits off of Sale in the two games and were directly responsible for eight of the 10 runs scored against him. Four of the five came against his fastball (the other was on a slider); in fact, 16 of the 20 homers he has allowed this season have come on the hard stuff.

His velocity is down a tick from his midsummer peak, but not enough to explain how the pitch went from a 2.0-percent rate of homers in at-bats that ended on fastballs last season to his 2015 rate of 4.5 percent. As is so often the case, the issue has come down to pitch command against a lineup sitting on heat. The above grand slam by Carlos Santana was the biggest blow, turning a 2-0 ballgame on Friday into a massive 6-0 deficit in the blink of an eye; the catcher's target is a bit volatile but the pitch was clearly intended to finish low and away, but Sale over-rotated the pitch, allowing it to leak over the inner part of the plate. It was the finishing blow in a six-run third inning, and though the big blast was set up by singles and an error (causing all six runs to be labeled unearned), the first out of the inning was a massive drive by Abraham Almonte to the deepest part of the ballpark. That out was a harbinger of things to come.

The drive by Almonte came on another misplaced fastball, given the catcher's setup on the low-inside corner of the zone and the pitch's location up-and-in to Almonte. The pitch was badly elevated, which is the surest path for fastballs to leave the yard. Sale elevated another heater in the seventh inning of Friday's game, this time to Francisco Lindor, and the rookie took the pitch out to the opposite field. It was intended to be under the zone, but instead Sale left it in the middle of the number two on the strike zone keypad, missing his spot by a couple feet in the vertical direction.

Sale only allowed three runs when he faced the Indians on September 7th, but all three came across via solo home runs, underscoring the frequency of Sale's punishable mistakes. Notorious lefty masher Ryan Raburn was responsible for two of the three jacks on the day, and though one of the blasts was on a well-located slider, the second blast came on—you guessed it—a fastball that finished far above its intended location.

The catcher set up down and in to the right-handed hitter, but a late arm caused the pitch to miss out over the middle of the plate, essentially served on a platter.

The Indians are not the only division rival that has knocked Sale around, as the Twins have also contributed to his recent struggles.

Game Stats vs. Minnesota

Date	IP	R	H	HR	BB	K	PC
Sep 13	3.0	6	9	1	0	3	71
Sep 1	6.1	4	9	0	1	10	113

Homers were not the problem in these two outings, nor was the longball center stage when the Twins rocked Sale for nine runs over three innings back in April, though Brian Dozier's three-run blast certainly expedited Sale's early flight. Sale has faced the Twins six times total this season, and though he has given up four homers in those half-dozen games, the glowing anomaly in his stat-line against Minnesota is the 46 hits that he has given up in 33 innings, with the resulting 7.71 ERA.

Verdict: Too early to worry.

The fact that Sale's issues with the Twins have spanned the length of the regular season leave open the possibility that the club has picked up on something that enhances its approach against him, while the ugly outings against the Indians boil down to a handful of missed targets. Elevated fastballs are the quickest route to free souvenirs, and pitches become elevated when the pitcher's trigger of trunk rotation is late. Such throws also tend to miss their intended targets to the arm-side, and though the Santana grand slam was a symptom of over-rotation (early trigger), most of his homers allowed have come on under-rotated fastballs to right-handed batters. Such issues just become magnified with a pitcher such as Sale who typically has excellent pitch command.

Patrick Corbin

Corbin was a big deal for about 15 minutes back in 2013, but a busted UCL and resulting Tommy John surgery took him out of the public eye as quickly as he had entered it. He returned to the big-league mound on Independence Day this year, and the early returns on his performance are glowing, in particular a 4.6-percent walk rate that is better than in either of his previous seasons. That's especially impressive considering that pitch command is typically the last thing to come back following elbow surgery.

Game Stats

Date	IP	R	H	BB	K	PC
Sep 19	7.0	0	5	0	5	80

Corbin shut down the Giants with incredible efficiency, requiring just 80 pitches to register 21 outs. He is on a strict pitch count, such that he hasn't thrown more than 91 pitches in any game this season, but Maddux-like efficiency has led to five consecutive quality starts despite pitch counts at or lower than 85 in each contest. He only managed two strikeouts through the first six innings against the Giants, but Corbin finished his dominant performance by striking out the side in the seventh frame. He even contributed an RBI single in what was a complete day on the diamond.

The southpaw hasn't walked a batter in any of his last four starts, has compiled 70 strikeouts against 13 walks in 75 innings this season, and has given up just three homers over his last 46 innings of work. His velocity has returned all the way to 2013 levels, averaging 93.1 mph on the fastball. He has paired his devastating slider and the movement on his fastball to keep batters on their toes, and while his seldom-used changeup theoretically leaves him vulnerable to right-handed bats, lefties are at his mercy.

Mechanics Report Card

Balance	50
Momentum	65
Torque	60
Posture	50
Repetition	60
Overall	B

For an explanation on the grading system for pitching mechanics, please consult this pair of articles.

The defining mechanical characteristic of Corbin's delivery is top-notch momentum, with a quick pace to the plate that he repeats extremely well. He starts the delivery with a move that generates forward momentum as soon as he begins leg lift and then continues to perpetuate through the lift and stride phases of his motion. The 65-grade momentum on the above report card matches his score from when I graded him during the 2013 season. He still uses a closed stride but exhibits a very strong delay of trunk rotation, allowing his hips to open after foot strike to increase hip-shoulder separation and support his plus torque. Some lefties use an exaggerated angle with their closed stride that prevents them from achieving full extension at release point, but Corbin's positioning with the lower half appears to be right in line with his personal signature.

Prior to surgery, Corbin stood out as a pitcher with the rare discrepancy of poor balance but strong repetition. Now he has a different discrepancy, as the balance has improved but the posture looks worse – Corbin does a better job of keeping his head positioned above the center-of-mass than he did in 2013, maintaining stability from first movement through foot strike, but he now invokes more spine tilt in the narrow time window between foot strike and release point. The fact that Corbin is up to his previously established levels of mechanical efficiency is a very positive indicator for his future performance, particularly his ability to rediscover the bold momentum and timing of stride that earmarked his delivery before he became forever linked to Tommy John.

Verdict: Swoon.

Corbin's performance thus far is legit and is supported by his stuff as well as mechanics. The stuff is back to pre-injury levels, critical aspects of his mechanics are already back to previously established levels, and he has flashed the upside for further improvement. Corbin will be a shrewd sleeper in next year's fantasy drafts, and don't be surprised if he's the Diamondbacks' best pitcher next season.