One thing about the "once in a lifetime status" for Mookie is, unlike players like Harper and Trout, Mookie was never a really highly regarded prospect. BA ranked him one time, and even then at #74, back before the 2014 season where was ranked below Garin Cecchini (#74). In 2013, Fangraphs had him at #15 in the Sox system. For some perspective, Brandon Jacobs was #13 that year and Anthony Ranaudo was #14.
So Mookie was really not so much a "once in a lifetime" player as much as he was a "came from nowhere" player who was just overlooked by every evaluating staff out there.
The big question for us Sox fans is, can we find another player to rise up so far from such obscurity? It's tough to picture, say, Hudson Potts or Connor Wong being so successful.
On the other hand, Betts numbers in the minors were good (.880 OPS in 1315 PA), but they were also far from legendary. Wong has a .852 OPS in 904 PA and Potts has a rather pedestrian .743 OPS in 1792 PA, but has also been very young for every level.
Obviously I don't think Wong and/or Potts are sure things to be the next Betts. But it is actually not out of the realm of possibility that someone is...
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