Scouting Mark Appel: the possible first pick overall in 2012

Stanford right-handed pitcher Mark Appel is one of the candidates to go first overall to the Houston Astros in the 2012 draft. With a four-seam fastball that touches 100 mph and sits 94-96, a two-seam fastball around 92-94 with a ton of arm-side run, a sharp slider from 82-84, and a changeup from 81-83 with plenty of depth, he has the tools to perform well in the big leagues. But there have been some serious concerns with his stats this year that are making a lot of people pause.

Where are the strikeouts?

As of April 9, Appel has only struck out 55 batters in 57 innings pitched despite his stuff (source: CollegeSplits). If you adjust for park/schedule (the Pac-12 is tougher than the average college conference), Appel projects to have 58 strikeouts in 57 innings pitched, which is not a huge improvement.

Pitchers who are projected to go with one of the top picks of the draft generally have gaudy strikeout totals, but they weren’t there in 2011 for Appel, and while they’ve improved some in 2012, it hasn’t been a huge increase.

The kinematics of Mark Appel

Similar to the Gerrit Cole and Danny Hultzen articles I’ve written, I’ve broken down Appel’s kinematics using high-speed video that I personally shot on April 5 when he pitched against the University of Washington.

Metrics for analysis

These will be the same metrics as the ones used in both the Cole/Hultzen analyses:

-Maximum knee height (absolute and relative to height)
-Degrees of shoulder abduction at foot contact
-Degrees of lead knee angle at foot contact
-Stride length at foot contact (absolute and relative to height)
-Degrees of maximum external rotation (MER)
-Degrees of lead hip flexion at ball release

Maximum knee height


Appel’s maximum lead knee height is 56.64 inches, giving him a relative measure of 75.5 percent of his standing height of 77 inches (error unknown). Research indicates that the best pitchers have a maximum knee height between 60 and 70 percent of their standing height, so Appel exceeds that to some degree. The idea is that if the lead knee is raised too high, the momentum down and toward the plate can be arrested or started late, though Appel doesn’t seem to have a problem with this.

Stride foot contact metrics

Appel strikes the ground with his heel first, which isn’t a problem, despite conventional thinking. There’s no correlation between loss of velocity and/or control issues with pitchers who land heel first.


  • Shoulder abduction (angle of elbow/upper arm) is about 84 degrees (error unknown). Research suggests elite pitchers are generally between 80-100 degrees at this phase of the delivery.
  • Lead knee angle is about 144 degrees (error unknown). Research suggests elite pitchers are generally between 125-140 degrees at this phase of the delivery. This is a minor red flag, because further down the delivery, you can see Appel firms up his lead knee and closes the angle a little more after heel strike.
  • Stride length is about 66.5 inches or 86.36 percent of his standing height. (error unknown). Research suggests elite pitchers generally stride 75-90 percent of their standing height.

Maximum external rotation


Appel’s MER is about 184 degrees (error unknown). Research suggests that elite pitchers tend to range from 170-190 degrees of “MER” throughout the delivery.

Hip flexion

At ball release, Appel’s lead hip flexion is about 87 degrees (error unknown). Research suggests that elite pitchers tend to be between 92-115 degrees of hip flexion at ball release, so Appel comes in a little short here. I think this is due to his very long stride, as the longer you stride, the tougher it is to flex forward at the trunk if you have blocked the front side with your leg. This can cause deceleration pathing issues in pitchers, but Appel doesn’t seem to have an excessive issue here.

A Hardball Times Update
Goodbye for now.

Wrapping up the kinematics

Here’s a review of the kinematics in a simple chart:


Appel is a little out of bounds on some of the markers, but I don’t personally think there’s much to be worried about.

Performance against Washington

I went to the game in Seattle with Jason Churchill, executive editor for Prospect Insider and contributor to ESPN’s coverage of young baseball prospects. He wrote up Appel on his blog and wasn’t too enthused with him, and I came away with similar thoughts. Appel couldn’t command his fastball in the first inning at 95 mph, so he dialed it down to 92-94 and relied heavily on his two-seam fastball against the power-heavy (and defensively light) lineup that Coach Meggs sent out there.

Though Appel shut out the Huskies after Jacob Lamb tagged him in the first for a two-run double, he only struck out three hitters, and he was unable to throw his slider for strikes early in the count. Appel relied on his two-seam fastball and changeup (81-83) to get induce weak contact in a relatively big ballpark, and though it worked, Appel is supposed to be a premier power pitcher with strikeout stuff, not a contact/finesse guy like his opponent, Aaron West (who I thought pitched pretty well, to be honest—take a look at high-speed footage of West on YouTube).

Appel has a relatively easy motion and not a lot of violence, and it lends itself to a pretty repeatable delivery. He’s a good athlete and fields his position well.

However, I kept thinking to myself, “If you have a 96-98 mph heater but can’t reliably command it, do you really have it at all?” It’s to his credit that he has the intelligence and humbleness to understand when he can’t throw his best bolt where he needs it, but that’s a trait you want to see from the fringe guys who have to maximize their stuff, not necessarily big-time prospects.

Bonus: Appel’s two-seam fastball

What did impress me was Mark Appel’s two-seam fastball that he commanded very well, getting it inside to righties on a regular basis and making them supremely uncomfortable and defensive at the plate. You can see how he releases it in this very slow animated image I created:


You can see how Appel drives the pinky-side of his hand to the plate in a supinated position, pronating through release and turning his hand over to get the massive arm-side run. Because of how Appel’s hand is positioned, if he fails to pronate at the right time, the ball will come out of his hand like a cutter, which explains a lot of references to his “cutter” or “two-seam cutter” that I’ve seen on various blogs out there. However, this doesn’t seem to happen often, and I didn’t see any cutter-like pitches from Appel.

Conclusion: To take him or not?

Whether or not I’d pick Appel with the first choice in the 2012 MLB draft isn’t an opinion I’m willing (or qualified) to form, but there are a lot of issues surrounding him that need to be examined before announcing his name. The teams picking at the top of the draft have their homework cut out for them.

References & Resources
My high-speed scouting videos from YouTube, available at Driveline Baseball YouTube Channel

Kyle owns Driveline Baseball and Driveline Biomechanics Research, and has authored The Dynamic Pitcher, a comprehensive book and video set dedicated to developing elite youth baseball pitchers. He is also a consultant for an MLB team and a major Division-I college program. Follow him on Twitter @drivelinebases or email him here.
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Shaun Parker
12 years ago

Now, let me start by saying I’ve never seen him pitch and I’m only going off of the measurements and pictures you have provided. After reading your article, in my opinion, the reason he does not miss many bats is due to the lack of downward plane created on his fastball. As he lands, his lead knee angle is slightly greater than the “norm”; therefore, it seems that he may have trouble “getting over his front side,” and simply goes forward as opposed to over. If he were slightly lower at his landing, he would then have to go up and over his front leg, driving his front side down, creating a more severe angle on his 4-seam fastball, as well as more depth on his 2-seamer and slider. To me, it looks as if he might lack some flexibility in his lower half. As you see by the above photos, his back side drag could be the cause of his heightened position at landing. He turns over his back foot (initiated by his hip and torso turn) but then he seems to drag that foot too far into his landing causing him to be more upright. Don’t get me wrong, you want to get away from your back foot to allow your hips to turn more effectively and efficiently, but if you get too far away from your back foot you create (in my opinion) too much back-side drag. This, in turn, will force a pitcher to drive through his front leg as opposed to up and over. In conclusion, he’s not missing bats enough because he is not creating enough depth on his pitches.

Kyle Boddy
12 years ago


Interesting take!

His four-seam fastball is pretty straight, but does have a little natural tail to it due to his arm slot.

I think he has pretty good flexibility in the lower half, otherwise he wouldn’t be able to stride that far or take a high leg kick without becoming unbalanced.

Shaun Parker
12 years ago

In hindsight, the flexibility is there as evidenced by your points above. It’s more the back side drag that concerns me. One could be flexible and drag there back side. There is no scientific evidence that suggests one is correlated with the other.

12 years ago

How are 149 pitch outings going to affect him such as the one last night?