I was on twitter, and I was able to check out a condensed start of Zack Wheeler in San Jose, courtesy of Splashing Pumpkins' Twitter (if you haven't checked out his blog, do so; it's one of the better ones out there and he also posts on Beyond the Box Score and MLB Daily Dish). He definitely showcased some wildness, but it's incredibly evident that he has electric stuff.
Being the curious cat that I am, I decided to go back and look up some of Wheeler's appearances from high school and Augusta on YouTube. It's amazing to see how much his delivery and mechanics have changed since his high school days. So, I'm going to post three videos and analyze all three.
Zack Wheeler in High School
A few things are pretty noticeable here. First off, he keeps his hands far away from his body in his twisting pitching motion. Furthermore, he has a pretty high leg kick, as it is almost Orlando Hernandez-esque. The only difference between him and Hernandez is that Wheeler keeps his glove high (around his head), while Hernandez kept his glove low around his waist (though Hernandez threw three quarter to sidearm, so that explains why his hands are so low). Another noticeable aspect about his delivery is how his back is mostly facing the pitcher. His shoulders are almost square to third base. While it does hide his pitches, he seems to be overcompensating with this twisting motion. Very few pitchers in the big leagues can do this and get away with it.
The most glaring quality of his windup has to be the sidestep with his right foot in his windup motion. He literally takes a full step to the left in his windup. Pay attention to this as you watch video of him in Augusta and how he makes that adjustment. In the stretch, he is mostly closed, with his left leg straight and lined up more toward third base when he gets set.
While the ball explodes off Wheeler's hand, there are a lot of moving parts in his pitching motion. That's not necessarily a good thing unless you're Tim Lincecum, but Lincecum is a superior athlete and has done so much to perfect his acrobatic pitching delivery that he can get away with it. Lincecum is an exception to the rule, not the standard. While Wheeler isn't a bad athlete, his violent delivery was an issue with scouts, and many felt that the Giants would have to refine it in order to protect him over the long term.
Zack Wheeler in Augusta
Wheeler's pitching motion is a little bit more contained in this video of him pitching in the Sally. While you mostly see game footage of him in the windup, you do get some telling things of his stretch pitching motion in his bullpen work.
What jumps out immediately to you his feet. In his high school days, he had a wider base, as his feet were about shoulder's length apart, if not a little more. He's closed up a little bit more, though it's not totally dramatic. Another change is that he's shortened up the windup, getting rid of the huge step to first base in his windup. I figured that would be one of the first changes to his pitching motion when he got to the big leagues, as it makes his pitching motion more refined and consistent.
The hands are also a lot closer to his body in Augusta and the leg kick isn't as high as well. He still twists a little bit and he is closed in the stretch, but it should be noted that it's less dramatic than it was in high school. Nonetheless, his delivery and mechanics look cleaner then they were in high school. He isn't moving around as much, and it isn't as violent as well. It's obvious the coaching staff made good strides with him in his transition from high school ball to Single A.
Zack Wheeler in San Jose
This is Wheeler at his best. His hands are closer to his body in his windup, the leg kick is lower and consistent, and he isn't exaggerating as much with his shoulders in his pitching motion. While in high school and Augusta his shoulders were facing more toward third, that isn't so much the case. His windup looks cleaner, and he seems to be exerting a lot less energy while still maintaining good velocity and movement on his pitches.
In the stretch, the biggest difference is that he's opened up a little bit when set. His left leg is more toward first base than third. It seems to have paid off, as he generates a good and quick delivery to the plate. He could be a little more consistent in his delivery out of the stretch (it does change a little from time to time, which accounts for his spotty command in this video, but that is to be expected for a 21 year old), but overall, you have to like the more compact nature of his delivery in San Jose in comparison to his more "moving" pitching motion back in high school.
Overall, the Giants pitching staff in the minors has worked a lot with Wheeler, and it's obvious that it's paid some dividends. He has changed as a pitcher in San Jose, and he is less raw now than he was a couple of years ago when he was a hot shot high school prospect. He still has some work. He needs to be more consistent of course in his delivery (especially in the stretch) and his command and control is still an issue, as you can see in the video of his May 11th start in San Jose. That being said, Wheeler has developed nicely and it'll be interesting how much he develops physically as he continues to climb up the Giants system. It's obvious that he has the stuff, size and tools to succeed as a Major League pitcher. It's just a matter of whether or not he'll be refined enough in his mechanics and command.