Take a moment to forget about the Brady Aiken mess and think about last year’s first overall selection. Mark Appel was supposed to be on the fast track. You aren’t supposed to struggle if you’re the first overall selection, and the 6-foot-5 right-handed starter with a prototype body had the look of a player who would move quickly, stopping only briefly in Lancaster and Corpus Christi to humble inferior hitters with his mid-to-upper-90s fastball. If you’ve been paying attention to his season, you know this hasn’t exactly gone as planned.

What has happened
First, appendicitis in January sidelined him for most of the spring. Regardless, the Astros aggressively sent him to Lancaster to begin the season. I was able to catch an early start of his, on April 10th, and was impressed with the raw stuff he brought to the table. Then 22, Appel showed a fastball that touched 98 mph, and paired it with a sharp, bat-missing slider (scouting report). Immediately after this start, on April 14th, Appel’s velocity dipped and only touched 91 mph. As has been well documented, the Astros installed a tandem or “piggyback” pitching rotation, where two “starters” would pitch back to back in the same game. Also, some pitchers would be subjected to only three days of rest, which happened to Appel in these two starts. This obviously took a toll on Appel, and there were rumors of shoulder soreness after the second start. He was sent to extended spring training to get some rest and have proper time to build stamina for the season. After returning, he had the worst start of his season on May 31st, surrendering 10 earned runs in 1 1/3 innings. Five days later, he was diagnosed with tendinitis in his right thumb and scratched from his next start. After getting the standard four days of rest (and sometimes more), he continued to struggle. Recently, the Astros made it public that Appel had a right wrist issue and received a cortisone shot. It’s unclear whether the thumb tendinitis is connected. I took in his start on July 10th with intentions of pin-pointing his problems.

What’s the problem
Appel has a smooth delivery with good momentum that drives toward the plate. It’s surprisingly easy for someone with his size. His filled-out upper body work well with his hips, which turn on time with the rest of his delivery. The extension he gets is very good, and if you pair that with a 92-98 mph fastball, it should create a problem for hitters to catch up to.

Unfortunately, that just isn’t happening. His fastball often plays soft—hitters are getting a very good look at this pitch for several reasons, the first being his command. Appel has walked only nine batters in 11 total starts, including the one on July 16th. Control isn’t his problem, as he has no issue throwing the ball over the plate and filling up the strike zone. He tends to be very “loose” with his command, meaning that when he tries to hit the low and outside corner to a lefty, the ball leaks over the plate or elevates. While that might work at Stanford with his plus raw stuff, it will does not work in the California League and certainly will not work at the highest level.

What might be causing this command issue is the excessive trunk tilt (lean) in his delivery (as seen below). I should warn you: I am not a biomechanist. This is something I noticed and it could help explain his struggles. The first figure shows what excessive trunk lean looks like in a pitcher, and for comparison purposes I took a screen shot of a video shot in early April this season. I tried to the find the video which showed him most square to home plate to make sure the lean was in fact excessive.


Photo cred: Crawfish Boxes

Appel has trouble getting the ball to the inside part of the plate to left-handed hitters. In my opinion, there is little doubt this lean in his delivery (which has increased since he left Stanford) is affecting his release point which, in turn, affects his command. “Contralateral trunk tilt,” as it’s referred to in this article, is not uncommon in pitchers and can even increase ball velocity, according to the American Journal of Sports Medicine. There is a strong, positive correlation between ball speed and trunk tilt. But, that study argued, there is risk involved too, and "future study is warranted to determine if this strategy should be encouraged or discouraged." Specifically, trunk tilt puts pitchers at more risk of injury, and "considering the prolonged time loss, we suggest that pitchers should avoid pitching with excessive contraleteral trunk tilt."

Could Appel’s delivery be source of his current troubles, and could his current delivery lead to more serious injuries? There obviously is not enough information without a full biomechanical evaluation.

Appel’s struggles are not simply explained by his delivery or command. What many other sources have noticed and written about Appel is his lack of pitchability. Appel’s stuff is good; in his July 10th start, Appel’s fastball touched 96 mph a couple times, sitting mostly 91-95. Early in his start, it was 94-96 mph. As the start progressed he seemed to tire, and kept pitching out of jams using mostly his slider and changeup. The fastball velocity dipped, and in his last inning sat only 91-93 mph. Most of the 13 hits off of him that evening were off his fastball, which was flat and up in the zone. He made no adjustment with his tempo throughout the game, keeping the same pace, which made it very easy for the opponent to time. He also made no adjustment with his pitch sequence, going to his fastball every time he was behind in the count, which was often a flat 93 mph get-me-over offering. He rarely attacked. It seemed he was simply going through the motions, and he didn’t show any emotion on the mound or in the dugout once he was removed from the game. While it’s not a requirement to show some fire, when you pitch like you’re scared of the opponent it doesn’t look good.

His delivery could be a problem; the command is certainly a concern; the pitchability and fortitude are in question; and he seemed to tire in both starts I witnessed. So, where do you go from here?

What comes next?
What do you do if you’re the Astros? Lancaster isn’t the best place to pitch, as the ball travels more there than any park in the California League. But he’s not just struggling at home. He’s already been to extended spring training, and he returned even worse than before. Double-A is an option, but not a very good one. He’ll face even stiffer competition, and he really just needs to focus on his delivery and aggressiveness on the mound. Quad Cities seems to the best bet to get him back on track, as he had success there last year. Pitching in more friendly confines could do him some good.

This is the first time Appel has ever faced adversity as a young man. He was star at Stanford, pitched well last season, and came into this season with the expectation that he could be in Houston by late summer. If he’s healthy, which the Astros keep reiterating is the case, then the blame for his abysmal season falls squarely on his shoulders. His fortitude is being questioned by everyone, including scouts who sit behind the net every night. In the end, it comes down to whether or not he can make the necessary adjustments on the mound. The Astros are going to give him every opportunity to succeed, so he needs to be the person that changes the course of his career.

I’m skeptical that he can make that adjustment because of every problem I highlighted above. I wrote a little more than two months ago that he could be a no. 2 starter, with a good chance that he ends up a no. 3 innings-eating workhorse. I definitely don’t see that anymore. I find it hard to even project him to become a major-league starter at this point. He certainly has the stuff, but any number of things could be affecting him. Is he hiding a shoulder injury? Is he simply not in good physical shape because of his short spring training? Is it purely mental? This is frustrating to think about, because only one person might really know the answer: Appel.

What will it look like if he does right the ship? It has to be a holistic approach taken by the Astros and Appel himself. It needs to start with his stuff; he’s simply not the same pitcher they drafted last season. The fastball that sat 94-97 and touched the high 90s has been inconsistent at best in 2014, and that needs to return. He needs to get healthy, and now. Whether that means shutting him down for a while or moving him to Corpus Christi, I’m sure I don’t know. Next, you work on the mental side of pitching. Watching videos of his starts at Stanford, he seemed in control and confident. He was able to make pitches whenever he needed it. He was able to pump 97 mph up in the zone for strike three whenever he needed to. That has been non-existent in Lancaster. If his stuff comes back and he regains his confidence on the mound, he’s a major leaguer, a damn good one. The ceiling is still there to become a no. 3 starter. If he continues to nibble, the stuff keeps playing down, and the Astros do nothing to help him, then he might not make it out of Triple-A. Based on my own eyewitness accounts, I’m leaning more toward the latter.

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I dunno. I don't like turning to speculation to conclude that a pitcher's ceiling has dropped after a small nagging-injury-riddled sample in the CAL league.

In the most annoying of ironic coincidences (from the standpoint of a writer), Appel pitched his best start last night against a good offense, hitting 96 in his final fastball (pitch 73), earning 7 K's and 0 BB's.

The Houston Chronicle reports (and as much as we miss Zachary Levine, Evan Drellich was a strong add to balance the inanity of the rest of their sports staff) that the team has been working on Appel's mechanics during his skipped start last week, and that sounds like it had an impact.

It's no secret around here that prospects aren't finished products. Appel is still a prospect, and thus requires development, or else he'd be in the bigs already. He's still got TOR stuff and a history of using it successfully. He was dominant last season in Quad Cities; outside of one stinker start, his ERA was 2.34, and so I don't see reason to pound a nail into his front line ceiling's coffin after fewer than 80 professional innings pitched.

Appel's need for development is no different than with any other prospect - even Kris Bryant currently has a 'needing development' issue: a 67% contact rate this season and 30% whiff/swing rate, which is even worse than Brandon Wood's, George Springer's, and a host of other players who have seen their ceilings questioned because of those issues. Appel's situation is highlighted by his pitiful run prevention counting stats and smaller sample of appearances, which try to give lie to his decent peripherals.

Note that I'm typing this without my Homer Hat on. It's just too soon to draw any conclusions other than that Appel needs more development than national prognosticators predicted.
If it's true they re-worked his mechanics (and that would be a big positive for his makeup as well because I've heard he doesn't want to change anything about his delivery), then I'm curious to see it in action. They've given him A LOT of time off between starts recently, so they're keeping him very fresh. Both positives. Again, I'm not writing him off. I liked the first start I saw. But the second was just so negative, and had so many problems that it was hard to ignore.

Remember, he still hasn't shown he can pitch every 5th day yet... Let's see how he reacts physically and mentally to the challenge.
A handful of starts, no matter how disastrous, doesn't change a guy's ceiling that radically. Especially a guy that has been scouted as extensively as Appel. His ceiling remains was it was 3 months ago. He just has more work to do to get there than we all thought, and the risk that he doesn't get there has gone up a bit.
Isnt what you highlighted in the picture also known as bad posture? And the head not over the knee spotty balance?
Yes; both his posture and balance have taken a step back from college and his appearances with Team USA. I had a chat with biomechanics guru Doug Thorburn about it.
From the look of the photo, I'd say the problem is lack of focus.
I appreciate the analysis and realize that BP is in the business of providing content but.....jump to conclusions much?

Two months ago, the guy was "as good, if not better than advertised in this look." Now he may not make it out of AAA because of a couple weeks in Lancaster.

Based on that analysis, are we to expect a piece about Conrad Gregor being the next Lou Gherig based on his time in Lancaster? Surely not, because we all know it's such a small amount of time.

I know it's in vogue to pile on the Astros and Appel lately, but it has jumped the shark at this point.
I would be much more optimistic about Appel if the stuff were crisp and remained crisp in both his starts, but they didn't. The velocity dipped, and he had a tough time putting the fastball where he wanted. It's not just that he needs more time like you all say, it's that he's a different pitcher than he was when drafted. I saw a report that he hit 96 mph in his last pitch last night, so that's a good sign. Still, it's a long way to go.
Understood, and I understand that BP's focus and the Astros' focus are different.

The thing I keep going back and forth on is his body language on the mound and in the dugout. Is he mature beyond his years and burning on the inside while showing a calm facade or does he just not have the fire? Who knows..
Chronicle reports he hit 97 last night. Potato Potahto.

In a couple comments you've indicated that you've only seen two of his starts. I find it surprising that just two looks would prompt this statement:

"I find it hard to even project him to become a major-league starter at this point."

Especially when you preface it by describing his "impressive raw stuff", three noteworthy injuries, and dominant performances prior to this year. Just seems reactionary and dramatic based on a very small sample, and I think that's why some of the comments are pushing back against this article.
That's fine, criticism is always welcome. Yes I've seen two starts. But reports from my colleague Ron Shah and talking with scouts in between and during his starts has helped paint a clearer picture for me. I probably should have mentioned that in my article. I've talked with numerous people about Appel and have listened to their opinions which helped form mine. I don't think this was dramatic or reactionary by any means. I stand by what I said in this article.
Why is this a shock to anyone? He was a constant underachiever in college. He was a poor draft pick then and his struggles should not surprise anyone with their eyes open.
Funny, I thought he was a consensus top 10 pick 2 years in a row. Actually, I thought it was top 5 and that he fell for signability reasons. Hard to say "why is this a shock" when people who make their living evaluatino amateurs for a professional baseball team didn't see it. Of course, it's possible I am missing remembering how it all went down.
Appel's struggles since having his appendix out remind me of Adam Dunn's disastrous 2011 after having his appendix out at the start of the year. Is there data on players having this surgery so we could assess patterns of performance decline (and, possibly, timetables for full recovery)?