When they come out of retirement, they don't age, they'll be the same age as if they retired 3 seasons afterwards. Example being, in one of my franchises a qb needed a 0.2 passer rating at the afc championship, I had 3 pick sixes in the sb on sim, and also my qb won mvp throwing 24 tds 8 ints. Yeah 25 was no where near perfect or as in depth as the ps2 gen of maddens.
