Mo Vaughn's last season was age 35, but he wasnt all that productive age 32. Cecil Fielder's last season was age 34, but he fell off a cliff at age 30-31 and his best years were 26-27. Prince is a better hitter than his dad, but he doesnt have more power or a better body - and he might have a worse body. The jury is still out on David Ortiz, obviously, but he was so-so last year and who knows if this year is a slump or the beginning of the end for him. He is age 33 this year. Even fat pitchers have had issues staying on the field after 32-33. Bartolo Colon and Sid Fernandez are two that come to mind, although David Wells is the exception. My Prediction for Fielder's career: He already is a poor first baseman. That will continue until he goes to an AL team, which he certainly will go to after his time with Milwaukee. He will likely get a 5-8 year deal on the FA Market taking him from age 28 to 33-36. He will be very good to great for ages 28-31. Age 32 and 33 he will be decent (25-30Hrs) and age 34-36 he will be below average and out of baseball by the end of his deal.