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The Hardball Times
When I describe “excellent” potential, I simply mean that the player has a non-trivial chance of being worth 10 wins above a replacement level player at his position during multiple seasons. In other words, these are guys who could be perennial All-Stars. These players usually have all the skills to become complete hitters and at least average fielders at their position.
When I describe “good” potential, I usually am describing a player who has the skills to become an above-average player at the position. Often, these players will have at least one major limitation that probably will prevent them from becoming top-tier players. When I describe “average” upside, I usually am describing a player with more than one major concern or limitation that suggests he probably will become an average player.
Players who are “close to their prime” usually are within a year of reaching a level of performance that will be among the five best seasons of their career.
I don't have a crystal ball and rely heavily on quantitative analysis of hitting and fielding performance to group players. These are simply estimates—any one of these players could be out of baseball at age 26 and any one could become a star. Mostly, I hope this list can help you identify exciting young players who are worth watching in the near future.
Excellent potential, close to prime
Joe Mauer
23 years old | Minnesota Twins
What's left to say about Joe Mauer? He could be to catchers what Cal Ripken was to shortstops.
Brian McCann
23 years old | Atlanta Braves
After a steady rise through the minor leagues, McCann experienced as strong a rookie campaign as anyone could have hoped for. At this time last year I noted that FIPro, my projection engine, suggested McCann was "ready for a breakout year in terms of power; 20-25 home runs is within reach." He didn't disappoint. Despite a career high of 15 home runs in a season before last year, McCann launched 24 in 2006 and emerged as one of the two best young catchers in baseball.