[nyy26wc]

Here's the results, using the Gambo/Spritze database.

1) Jim Kennan, 22, 17
2) Jim Thome, 21, 20
3) Chipper Jones, 22, 21
4) George High Pockets Kelly, 21, 19
5) Magglio Ordonez, 22, 23
6) Bug Holliday, 18, 22
7) Johnny Bench, 19, 21
8) Will Clark, 19, 22
9) Ray Grimes, 24, 26
10) Chuck Knoblauch, 18, 22
11) Moose McCormick, 21, 23
12) Jimmy Wood, 25, 27
13) Chief Zimmer, 21, 23
14) Al Wingo, 19, 21
15) Dale Murphy, 22, 20
16) Randy Milligan, 17, 25
17) Larry Doby, 21, 23
18) Jim Wynn, 18, 21
19) George Pinkney, 23, 22
20) Ed Morgan, 22, 24
21) Johnny Damon, 22, 21
22) Doc Gessler, 20, 22
23) Yogi Berra, 22, 21
24) Lou Whitaker, 22, 20
25) Dizzy Dean, 18, 20
26) Carlos Santana, 17, 24
27) Hank Leiber, 20, 22
28) Brett Lawrie, 17, 21
29) Olmedo Saenz, 17, 23
30) Alvin Davis, 19, 23

No fixed rule here about players being 2 years younger than they were in their real first year.

But, there's also a case of 30 players out of 30 all debuting in the draft at an age other than their 1st year in the majors. That can't be just attributed to random chance.