I think there are some problems with this. I agree the circumstancial evidence is there, though in Joes case, the jump occurred as he was going into his prime, which is not terribly unusual (see Plouffe, Trevor or Bautista, Tony). That said, MLB has been testing for PEDs, and if there are PEDs that can do what they did to Mauer, then why in the world was Ryan Braun ever caught? Every hitter in baseball would be on those. The other big thing is that Mauer played the next season in Target Field. The Metrodome was very friendly to the type of hitter Joe is and many of the HRs it recorded were warning track fly balls in TF or doubles in the gap/off the wall. I cannot give you an explanation for this, as the dimensions are fairly similar, but again the stats speak for themselves. Mauer was also in very good health in 2009. He had that going for him in 2010 as well, but has not had it hte last couple of years. Even though he's put up fairly respectable numbers, he doesn't seem quite himself. Not sure why that is. I do think that another part of it is that hte league has figured him out... why he doens't adjust is beyond me. During the Tiger series, the Tigers announcers made a big deal that Mauer was one of the top 5 in the league in not swinging at the first pitch (doing so less than 10% of the time), and so pitchers would grove a batting practice fastball in on him. He was always behind in the count. Mauer hasn't adjusted to this, and I'd add neither has Gardy... When Revere was on with 2 outs and Mauer was at the plate, I'd think Gardy would take advantage of this and call a hit and run... but nope.