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Mark Appel | RHP | Stanford University
Ht/Wt: 6-5/215 | B/T: R/R | Age at Draft: 21y 11m

Grading Out:






















Overall Future Potential:


Adjusted OFP:


Appel in 140 characters or less:

Sturdy build w/smooth actions; potential for three + or better offerings, pot. ++FB; improved command; good workload; front-end w/high floor.

Physical Description:

Nice broad, physical frame with durable build; solid athlete, controls limbs; solid flexibility; solid actions off mound. 


Appel is clean to a fault in his delivery, historically losing some deception but making up for it this year with more consistent execution and better overall command.  The ball is still shy of “difficult to pick up,” but his sequencing is less predictable this spring than it was in 2012, and there is more deception in his release on his secondaries.  Appel paces well throughout his mechanics and has had no difficulty regularly repeating his delivery.  On occasion, he will drop his arm slot for both his slider and changeup, causing both offerings to lose deception.  Out of the stretch, the Stanford ace is 1.20 to 1.28 to home, and alters timing such that base runners have a difficult time getting quality jumps.   


Fastball –  The heater is a true plus to plus-plus offering, sitting 93-96 mph and climbing to 97/98 mph on occasion.  It is most effective down on the zone, traveling on a steep plane, and Appel can turn over the two-seam to produce arm side run.  He holds velocity into the late innings and moves the pitch around the zone with limited difficulty.

Slider – At its best, Appel’s slider can flash plus-plus, but more regularly vacillates between average and plus, depending on the game.  The pitch is a mid-80s weapon that displays tilt and late bite from the waist down, but can flatten out and soften higher in the zone.  He’s better spotting the pitch in the zone than inducing hitters to chase, but as he continues to improve his sequencing he should be able to utilize the pitch to expand the zone against advanced hitters, as well. 

Changeup – Another plus offering, Appel’s offspeed dovetails with his arm side fastball action and comes with arm speed and trajectory deception.  When clicking, he can produce late fade and tumble and a lot of empty swings.  A low-80s offering, the velo delta is more than adequate as a change of pace, and he is comfortable throwing the pitch in any count and in any game situation.


Appel has always graded out well, but this spring he has dramatically improved his aggression in the zone—a hole in his game that often limited the utility of his stuff in the past.  This spring, the senior standout has taken his game to the next level, dropping one-half of a pitch off of his average pitches-per-batter and working ahead much more consistently.  The results speak for themselves, as Appel has improved his strikeout rate, lowered his walk rate, and decreased his batting average against.  To the extent Appel has run into issues with his stuff on a game-by-game basis, he has reacted admirably, rotating his pitch selection to find the most effective weapon and battling.  Houston’s decision as to who they will select with the first overall pick in the draft is in all likelihood down to Appel and Oklahoma’s Jonathan Gray—two collegiate arms with front-end stuff, impressive spring production, and a good chance to chew through innings.  Appel has less room for growth in his stuff than does Gray, but the strides he has made this spring in pounding the zone, and particularly the lower shelf, help assuage fears that Appel might lack the killer instinct necessary to headline a Major League staff.  He should be off the board in the first couple picks, and it would be a surprise if he were not a fixture in his draft org’s rotation by mid-2014.

Projected position: Front-end starter; #1/#2

Suggested draft slot: Early-1st Round; consideration for top 5 overall


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I saw Appel pitch in Houston against the Rice Owls this Spring, a game in which he flashed his plus stuff but never seemed to get comfortable. He also failed to back up a base more than once, which eventually led to 2 runs being scored. What is your take on his general makeup/ maturity?
I was at the game as well -- it was not a good start for Appel. I'd say it's important to keep in mind that on field demeanor, particular in one-off instances, is seldom evidence of good or bad makeup.

I have seen a good amount of Appel over the last three years and will say that his overall approach has been more aggressive this year than in years past. In previous years I questioned Appel's desire/ability to take ownership of his stuff and just go out there and shove it for 9 innings. Those concerns have been somewhat quelled with his 2013 performance.