A: Hank Aaron - MLB's all-time home run king*.
B: Ernie Banks - Let's play two.
C: Steve Carlton - Phillies legend.
D: Andre Dawson - Eight Gold Gloves, four Silver Sluggers, and one of the more memorable SI covers of the era.
E: Dennis Eckersley - Closed for Oakland when they were my #2 team.
F: Mark Fidrych - The Bird flew high, but the landing was rough.
G: Tony Gwynn - San Diego State basketball's all-time assists leader.
H: Trevor Hoffman - Cue AC/DC.
I: Monte Irvin - Negro League star and World War II veteran.
J: Derek Jeter - Bo Jackson didn't last long enough.
K: Al Kaline - I love the smell of Gold Gloves in the morning.
L: Kenny Lofton - 622 steals and four Gold Gloves.
M: Tug McGraw - Phillies legend. Got his autograph.
N: Phil Niekro - Hall of Famer who pitched 24 seasons in the bigs.
O: Amos Otis - 341 steals and three Gold Gloves.
P: Chris Pritchett - Went to the same h.s. though he had graduated by the time I started. Saw him contribute to a playoff win by sending the game into OT with a half-court buzzer beater.
Q: Dan Quisenberry - Good pitcher / weak letter.
R: Jackie Robinson - The man.
S: Mike Schmidt - The legendest Phillies legend of them all.
T: Jim Thorpe - American bad ass.
U: Chase Utley - Phillies legend.
V: Justin Verlander - Two Cy Young Awards and three no-hitters.
W: Devon White - 346 steals and seven Gold Gloves. Plus, we share a birthday.
X: Joe Jackson - As Kevin pointed out, there has not been a major leaguer with a surname starting with X. So I'm going with an extremely talented and controversial illiterate player.
Y: Robin Yount - MVP as a shortstop. MVP as a center fielder.
Z: Don Zimmer - 65 years in professional baseball.
Anyway, I have to go remove Fuji from my will for picking Suzuki over Schmidt.
Credit to Kevin for getting this topic started.