Mike Trout, Andruw Jones, Alex Rodriguez, Ken Griffey Jr., Ceasar Cedeno, John Bench, Vada Pinson, Frank Robinson, Al Kaline, Mickey Mantle, Ed Matthews, Ted Williams, Arky Vaughn, Mel Ott, Jimmy Foxx, Rogers Hornsby, Ty Cobb, Sherry Magee.
I think most reasonably serious baseball fans should be familiar with almost everyone on this list, as most of them are in Cooperstown. Of the ones who aren't:
Cesar Cedeno certainly looked like a HOFer through 26 or 27, but tailed off, I think becasue of injuries. In any case, his 52.7 rWAR is better than many actual HOFers.
Pinson's career was similar to Cedeno's, with 46 rWAR through 28, but only about 8 afterwards. Career value of 54 is better than a number of HOFers.
And Sherry Magee may have been better, relative to his peers, than either Cedeno or Pinson. His raw numbers aren't that impressive because he played in the deadball era, but had some very, very good years and a career 137 OPS+ (98th all time). In 1910 he led the NL in BA/OBP/SLG/OPS/OPS+/total bases/RBI.
Most of you are familiar with Andruw Jones, who was a better version of the three guys I just described - great 20s before fading, but an even higher total.
So the floor for a position player with 10 rWAR through 21 is currently "has a plausible case for the HOF". Every single player who reached that threshold had a very long, very productive career.
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