Over the history of the game, most top players reach the big leagues by 23 or so, with many a year or two earlier than that. You hear a lot of times that people will say, "oh back in the old days, guys had more time to develop etc." That's really not true for the best players. That may be true for the best payers but what is the average age for the normal players? I seem to remember something like 25 or 26 as the average age to break into the majors but that could be way off. It is true that many of the best and brightest of all time can play at a high level early on but I don't think anyone is saying the likes of JJ Hardy, Cory Hart, Manny Parra and Rickie Weeks are in that category. This core, though very talented as a whole, is more along the lines of good quality major league players. What makes them so good is they are all above average. I don't think any of them qualify as historically the best like Yount or Molitor. So their age progression should probably be viewed as such not as the best of the best of all time.