The Houston native went unsigned last year as a junior after falling to the Pirates with the 8th overall pick. Appel is a client of Scott Boras and his signability will still be a question this season, but as a senior with no leverage in a weak draft, he should go in the top five and sign quickly. A few things caused many clubs to rank both Kevin Gausman (4th overall pick, Orioles) and Kyle Zimmer (5th, Royals): the lack deception, plane and life on his fastball, his stiff upper half and his at times passive approach that contributes to results not matching his raw stuff.
Last season and in his first appearance this season against Rice, Appel was 94-97 mph early and 91-93 later in outings with diminished command as he tired. Against Fresno State, he was a tick better at 95-98 mph early and a couple ticks better late at 92-95 touching 96 in the 8th inning. He was also more aggressive with sequencing and location versus the Bulldogs, staying on top of his heater with good plane and solid life down in the zone that generated a good number of groundballs. I think it just happened to be a good stuff day for Appel as he was a tick better across the board and he's normally up in the zone more due to a drop-and-drive delivery gives him a diminished plane and combines with an inconsistent ability to get over his front leg to make him a flyball type pitcher.
As his velocity was better, so Appel's slider was sharper last weekend. The pitch is best at 85-88 mph and regularly flashes plus potential with good tilt, length and late bite. The shape of the pitch and consistency of the bite will vary but this weekend Appel was able to repeat it more effectively. The utility of the pitch played up as he stacked fastball-slider combination on both sides of the plate to baffle Fresno State hitters and threw a number of sliders I graded as a 65 and a few that may have been 70s. Again, I think this was a bit of an aberration and Appel doesn't have much projection, but this is in the tank and could come back. He also rarely throws an 81-83 mph curveball that is just a softer and more vertical version of the slider that's a clear fourth option to change eye level on the third time through a lineup.
Early in the game, Appel threw this pitch a little too hard and it has splitter type action at 85-86 mph but wasn't as effective as it was late in the outing at the normal 80-83 mph. The pitch has excellent deception and bottom with arm side fade and flashes plus potential but it was a clear third option so the feel waned from inning to inning. It was impressive to see Appel dominant with two pitches then have another plus pitch in his back pocket to save for later in the game.
If it sounds like I'm raving a little too much, it's because I saw Appel's low point when he was hammered by Florida State in super regionals last year but also because this was probably the best stuff he's ever had. I talked to him after to the game (audio will be posted soon) and he seemed a little surprised. The pitcher he was tonight—two plus-plus pitches with a plus change, above average command and a groundball tendency—is a true #1 starter that would've stymied most big league lineups.
The problem is that every other outing in the last two seasons, Appel has been a potential #2/3 starter with plus stuff, average command a flyball tendency and results that don't match the stuff. When this happens once, you have to assume it won't happen again, but the approach Appel was emboldened to use with the stuff could come back and would make him a much better prospect.
Scouts' catchall phrase for not playing up to your stuff is "lack of a killer instinct." Appel said all the right things after the game to suggest he would be different going forward, but it's hard to believe until it happens regularly. In a lot of ways, he's like a pitching machine off of an assembly line. He has ideal size and all the big signposts in his delivery are either solid or great: balance, posture, arm action, front side, extension, effort, landing, aggressive delivery.
Being off an assembly line also comes with its negatives, as Appel isn't very deceptive with everything being so clean, though he takes a bit of an angle to the plate to try to help that. Also, having an aggressive drop-and-drive delivery to maximize arm speed also causes some problems, mainly tied to his stiff upper half. If you watch him walk around the mound, Appel has a strong, loose and athletic pitcher's lower half but walks around with poor posture and has stiff shoulders. When you look at his delivery slowed down, he's doing a lot of things well in his delivery but he isn't athletic enough to always repeat his delivery and hit his spots.
He can over stride at times and pitch against his front leg particularly when fatigued. His high arm slot limits the life on his fastball but the plane created by this slot is limited by a delivery that doesn't take advantage of his size. Appel has a maxed-out frame and isn't getting any looser so some of what makes his stuff so good will hinder his command.
I have Indiana State's Sean Manaea (report and video) neck and neck with Appel (video) and will break them down side by side in another article. It will be instructive to monitor Appel's strikeout rate against good lineups later in the season to see if his more aggressive approach is sticking—the main complaint of scouts. There are clear pluses and minuses to Appel but the pluses are incredibly hard to find, particularly in a weaker draft and I can't see him getting out of the top three picks this season with number one starter potential still possible.