Mark Appel, the No. 1 overall pick in the 2013 Draft, is taking a leave from baseball .
Selected by the Astros ahead of Kristopher Bryant, who went No. 2 to the Cubs, Appel was acquired by the Phillies in a seven-player trade that brought Ken Giles to Houston in December 2015. Appel had surgery to remove a bone spur from his right elbow in 2016, then missed two months last year with a right shoulder strain before Philadelphia designated him for assignment to remove him from its 40-man roster in November.
Appel has had only sporadic success in the Minors, going 24-18 with a 5.06 ERA and 315 strikeouts in 375 1/3 innings in five seasons. Should he not return to baseball, he would join Steve Chilcott (Mets, 1966) and Brien Taylor (Yankees, 1991) as the only No. 1 overall choices to conclude their careers without reaching the big leagues since the Draft began in 1965.
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This question refers to my story on prospect doppelgängers, where I looked at MLB Pipeline's tools grades to see which recent elite prospects most closely mirrored the 10 best prospects on our new Top 100 Prospects list. Angels two-way sensation Shohei Otahni paralleled a combination of Yu Darvish and George Springer, Braves outfielder Ronald Acuna had similarities to Gregory Polanco (though he was far more advanced at the same stage of his career), and so on.
Here are the doppelgängers for the prospects we ranked 11-20 on the Top 100:
11. Francisco Mejia, C, Indians (60 bat, 50 power, 40 speed, 70 arm, 45 defense)
Willson Contreras, C, Cubs, 2016 midseason (60 bat, 50 power, 40 speed, 55 arm, 50 defense)
Like Contreras, Mejia is a bat-first catcher, albeit with a much stronger arm.
12. Brent Honeywell, RHP, Rays (60 fastball, 55 slider, 45 curveball, 65 screwball, 60 changeup, 60 control)
Danny Hultzen, LHP, Mariners, 2013 preseason (60 fastball, 60 slider, 60 changeup, 60 control)
There's no match for the screwball and this is righty versus lefty, but Hultzen had four plus attributes before he got hurt.
13. Walker Buehler, RHP, Dodgers (70 fastball, 65 curveball, 60 slider, 50 changeup, 55 control)
Zack Wheeler, RHP, Mets, 2013 preseason & midseason (70 fastball, 60 curveball, 60 slider, 50 changeup, 60 control)
Buehler had Tommy John surgery before getting these grades, while Wheeler's elbow reconstruction came after his.
14. Bo Bichette, SS/2B, Blue Jays (70 bat, 55 power, 50 speed, 55 arm, 45 defense)
Nick Castellanos, 3B, Tigers, 2014 preseason (70 bat, 60 power, 40 speed, 55 arm, 50 defense)
If we used current Top 100 guys, Bichette would stack up well with No. 5 prospect Gleyber Torres and No. 7 Nick Senzel, albeit with less defensive skills.
15. Brendan Rodgers, SS/2B, Rockies (60 bat, 55 power, 50 speed, 60 arm, 50 defense)
Alex Bregman, SS/3B, Astros, 2016 midseason (60 bat, 55 power, 50 speed, 55 arm, 50 defense)
Bregman was also our best match for No. 8 prospect Fernando Tatis Jr.
16. Mitch Keller, RHP, Pirates (65 fastball, 55 curveball, 50 changeup, 60 control)
Dylan Bundy, RHP, Orioles, 2015 midseason (65 fastball, 60 curveball, 55 changeup, 60 control)
Before he had Tommy John surgery in 2013, Bundy had the highest grade total (three pitches plus control) we've ever given at 270 (also matched by Gerrit Cole).
17. Kyle Tucker, OF, Astros (55 bat, 60 power, 50 speed, 55 arm, 45 defense
Nomar Mazara, OF, Rangers (55 bat, 60 power, 40 speed, 60 arm, 50 defense)
Mazara became an everyday big leaguer at 21 -- which will be Tucker's age this season.
18. Alex Reyes, RHP, Cardinals (75 fastball, 60 curveball, 55 changeup, 45 control)
Tyler Glasnow, 2015 preseason through 2016 midseason (75 fastball, 60 curveball, 50 changeup, 45 control)
Glasnow was also our doppelgänger for No. 10 prospect Michael Kopech.
19. MacKenzie Gore, LHP, Padres (65 fastball, 60 curveball, 55 slider, 55 changeup, 55 control)
Julio Urias, LHP, Dodgers, 2016 preseason & midseason (65 fastball, 60 curveball, 60 changeup, 55 control)
If we went with a righty, 2014 preseason Jameson Taillon is a perfect match except for not having a slider.
20. Royce Lewis, SS, Twins (60 bat, 50 power, 70 speed, 50 arm, 50 defense)
Trea Turner, SS, Nationals, 2015 midseason through 2016 preseason (55 bat, 40 power, 75 speed, 55 arm, 50 defense)
As with Turner, there are questions as to whether Lewis sticks at shortstop or winds up in center field.
Daniel, who sent us this question, is the managing editor of DRaysBay, so we'll throw in our highest-rated Rays position prospect as a bonus:
22. Willy Adames, SS/2B, Rays (55 bat, 50 power, 50 speed, 60 arm, 60 defense)
Xander Bogaerts, SS, Red Sox, 2013 preseason & midseason (60 bat, 50 power, 50 speed, 60 arm, 60 defense)
This is one of the closest comparisons, and they have similar physical builds as well.

James covers Yankees Minor Leaguers for Pinstriped Prospects, so he knows New York has one of the deepest farm systems in baseball. How deep? Check out my answer in the video at the top of this story.

Tucker (24th overall in 2014) and Newman (19th overall in '15) are both shortstops drafted in the first round by the Pirates, and one of them soon will depose Jordy Mercer and take over as Pittsburgh's long-term answer at that position. Newman, who's 23 and finished last year in Triple-A, will get to PNC Park first at some point in '18 but Tucker, who's 20 and already has reached Double-A, will be the better player in the long run.
Newman, who hit .267/.311/.363 with 11 steals in 2017, is one of the best contact hitters in the Minor Leagues. But Tucker is no slouch at the plate (.275/.358/.408 with 47 steals) and he has more gap power, is a step quicker and possesses more range and arm strength at shortstop. When he's ready to join the Pirates in '19, Tucker figures to push Newman over to second base.

I wouldn't project that Varsho, Wilson or fellow D-backs prospect Jazz Chisholm necessarily will make our midseason Top 100, but they're all talented enough to make a run at it.
Varsho, who batted .311/.368/.534 in Class A Short-Season ball during his 2017 pro debut, is a very athletic catcher with plus speed and the ability to hit for average and power, though his below-average arm works against him defensively. He's the son of former big league outfielder and current Pirates scouts Gary Varsho and was named for Darren Daulton, his father's teammate on the Phillies.
Wilson hit .295/.383/.446 with 15 steals in low Class A last year. He has some of the best raw tools in Arizona's system and is starting to translate them into skills. Wilson has plus speed, average power potential and a chance to stick in center field.
A torn meniscus in his right knee limited Chisholm to 29 games last season, when he batted .248/.325/.358 in low Class A. He has surprising power for his size (5-foot-11, 165 pounds) and a shortstop, plus the actions and arm strength to remain at that position.