It's not based on "career" in my opinion. It's based on who you'd want as your first baseman RIGHT NOW. Given the choice of picking Lee or Pujols, I think everybody outside of Chicago would take Pujols. Heck, even if you base it on last season, you'd probably want Pujols (based on Win Shares). No, if you base it on last season, I'd want Lee who was better offensively and defensively. Pujols actually had slightly higher Win Shares, which takes defense into account. You can use other measures that favor Lee, but there was no clear-cut favorite, in my opinion. Such as H, 2B, HR, BA, SLG, OPS for hitting and F%, assists and Zone Rating for fielding... All of which are figured into the Win Shares stat that I've already mentioned.