[農場] Pitcher Analysis: Clayton Kershaw

看板Dodgers作者abc12812 (abc12812)時間17年前 (2008/05/26 12:07)推噓1(1推 0噓 2→)

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http://tinyurl.com/4s5r8g Clayton Kershaw, a 20-year old phenom in the Dodgers organization, is one of the top pitching prospects in the nation. Today (5/25), Kershaw made his MLB debut against the St. Louis Cardinals. Millions of Dodgers fans watched to see the kid touted as the next Sandy Koufax and hoped that the young lefty would live up to the hype. He didn’t disappoint. Kershaw gave six solid innings of work, striking out seven, walking one, and scattering five hits, giving up just two runs in the process. Unfortunately due to some defensive misplays (Dewitt’s throw home, Loney’s juggling of a pop fly), Kershaw got stuck with an extra run he perhaps didn’t deserve. The Dodgers maligned offense couldn’t give him three runs, so he left the game tied, unable to get a win. However, by any measure, Kershaw’s debut was a success. He showed off excellent command of his 94 mph fastball - dialing it up to 96 on plenty of occasions - and maintained his velocity even as he eclipsed 100 pitches in his start. His 72-76 mph curveball was devastating, as he was liable to throw it in any count to any hitter, burying it in the dirt for swinging strikeouts and simply looping it over the plate for a get-me-over strike. I saw an outstanding young pitcher with a ton of promise today. Let’s take a look at what Clayton Kershaw has done in the past and let’s look to the future as we analyze his mechanics… Kershaw’s Statistical Analysis The Dodgers knew they had something special on their hands as soon as they assigned Kershaw to rookie ball at age 18 in the Gulf Coast League. Kershaw pitched only 37 innings, but struck out 54, walked only 5, and gave up no home runs, netting a 1.95 ERA and 0.89 WHIP. At age 19 he rocketed through A-ball in the Midwest League, posting 134 strikeouts, 50 walks, and 5 home runs allowed in 97 innings (2.77 ERA, 1.25 WHIP) and finished the year in AA, throwing 24 innings with a 29:17 k/bb ratio but allowing four home runs (3.65 ERA, 1.38 WHIP). Those stats are unbelievably impressive for a young prospect, much less a 19 year old in AA ball! However, Kershaw was not satisfied. He would return to the Midwest League in 2008 at age 20, where he would throw just 43 innings before getting called up to the MLB to start. In his 2008 stint in AA, he would allow no home runs while shaving his walk rate down, as he posted a 47:15 k/bb ratio (2.28 ERA, 1.08 WHIP). By any statistical measure, Clayton Kershaw has nothing left to prove in the minors. He depressed XBH rates, he struck out more than a batter per inning, and he shaved his walk rate even farther down. His command and control are exceptional, and his stuff is outstanding - pairing a red-hot 96 mph fastball with a devastating 12-6 72-76 mph curveball and flashing an average changeup with good fade (the only pitch he needs to work on to help get the tough right-handed hitters out). However, it is important to note that Kershaw is only 20 years old and threw just 122 innings in 2007. Assuming the Dodgers bump up his innings limit to 140-150 this year, he still won’t be ready to fully slot into the rotation until 2010, though nothing aside from injuries will stop him from throwing 160-175 innings in 2009. His performance is too good to leave in the minors, something the Cincinnati Reds should learn from (Jay Bruce). The Dodgers should hopefully realize the talent they have in Kershaw and treat him accordingly - to rush him to the majors and place a large workload on him would be irresponsible. Kershaw’s Mechanical Analysis Here’s video from his MLB start: And here’s video from him in the minors (source: Hardball Times): Let’s break down his mechanics, point by point. Arm Action This is Kershaw at footstrike. As you can see, his PAS elbow is below the level of his shoulders, a very good sign. Furthermore, his arm is up and through the horizontal plane at the ready/high-cocked position, another good sign. He exhibits horizontal abduction of the shoulders, taking the elbows behind the body - also known as “scapular loading.” Though I think this stresses the anterior muscle groups of the shoulders, there is significant evidence that shows “scap loading” is a major component of velocity. Furthermore, plenty of pitchers exhibit this horizontal abduction and have remained healthy throughout the years - Greg Maddux is just one of many examples. As I have said before, there is a model pitcher at RPM Pitching who shows very little scapular loading and throws 90+ MPH by actively involving muscle groups that are typically used passively to decelerate the ball (latissimus dorsi, Pronator Teres), but it’s just a sample size of one and the results are not yet public. However, I digress. Note Kershaw’s arm angle in this frame: See how it’s bent towards his head? This will help prevent Kershaw’s arm from “flying out” and it also makes it easier for him to pronate through release (if he does this) to prevent his ulna bone from slamming into his olecranon process. It will also help stop inflammation of the medial epicondyle (sore elbow), which is caused by supinated releases of pitchers. Here’s a slowed-down clip of Kershaw’s arm action: Note the pendulum-swing type arm action as he starts with the glove high but brings it down to waist-level at hand break; a major plus. Also watch as he keeps his weight back and rides that back leg as he powerfully strides into footplant. In the footstrike still photo above, you can see how he is turning the hips well ahead of the shoulders (look for the belt buckle to face home plate while the shoulders remain closed) - this is a major component of velocity. Kershaw also does not take the ball laterally behind his body in reverse rotation. Not only will this reduce the load on his shoulder, but it will increase the perceived velocity of all of his pitches. Here’s what I mean: The hitter won’t see the ball until the second-to-last frame - right before ball release. This makes it really hard to pick up the type of pitch and will increase his deception. Kershaw’s arm action is Excellent. He embodies great mechanics from both a medical/injury prevention outlook and a performance view. Nothing more to say on this topic. Tempo As Alex Eisenberg points out, Clayton Kershaw is a bit slow from maximal leg lift into footplant for a power pitcher, clocking in around 29-30 frames. I’d like to see him pick up the pace to help take the load off his arm/shoulder, and possibly gain a tick or two on his fastball, but his arm action is so clean that I wouldn’t want to mess with anything here in fear of negatively affecting his other outstanding qualities. Therefore, while his tempo grade is Poor, I can’t recommend any changes. Ball Release A major component of the ball release phase is the ability to hide the ball well, or add to your deception. As I covered in the Arm Action segment, Kershaw does an outstanding job of this by not reverse rotating his shoulders as he delivers the pitch and also keeps the arm bent towards his head, ensuring the arm does not fly out and let the hitter pick up the ball earlier. As such, I’m going to combine the Ball Release / Followthrough phases together by using these clips: Immediately upon viewing these clips, I noted the intent of Kershaw - similar to that of Max Scherzer - he bends his back and points his PAS shoulder at the target while pulling down with his head. These are all great aspects of his delivery. Note how in the first clip Kershaw is maximally rotating his shoulders. This will give him a great setup for the followthrough and recovery phases of the delivery. Kershaw does a good job of firming up the front side as his chest comes to the glove and he shows no sign of actively pulling with the glove arm. Actively pulling the glove to the chest can cause flyout and a reduction of velocity, and I do not recommend pulling the elbow back as most amateur pitchers do; I prefer pitchers to focus on bringing the hand to the shoulder. Kershaw’s arm follows through completely to his back pocket and he exhibits no signs of actively braking his arm. Combine this with his great intent and maximal shoulder rotation after release, and you have all the ingredients for an Excellent ball release phase and an Excellent followthrough phase. Conclusion Dodgers fans, you have a stud pitcher on your hands for the next few years who exhibits all the performance of a Sandy Koufax without the mechanical flaws. If the Dodgers avoid overworking him in any given start and limit his innings increases throughout his career, you’re going to have one hell of an ace. Let’s just hope that Joe Torre doesn’t take forever to trust his young talent as he often does with rookies. -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 140.112.5.3