With the source of the problem explained, the only solution I can give you is to get better reserves and a doctor with massage speciality. The better reserves can make a minor difference, but I have a 99k center with a 67k backup and he still makes 44+ minutes a game because of his proficient stamina. Luckily he can manage high minutes a little better, but that doesn't compensate the big amount of minutes he gets in 2 games, so I try to just start him in 1 game when I can.