Reminder that after next sim (9/1 in game) ACTIVE MLB rosters can expand to 40 from 25. Keep in mind any player with a MINOR LEAGUE CONTRACT will be assigned a 40-man major-league deal if they are promoted.
This is a good chance for mlb contracts in the minors to get up and get some at bats...they provide rest for starters during the month before the playoffs (or are trial versions for following seasons, etc). You also can call up rookies with minor league deals that you are 100% sure that you're wanting in the bigs to start next spring and get them some at bats.
I personally advise against promoting anyone that isn't already on the 40-man roster, unless he is a junk player and you're just trying to see if he is worth holding on to and have nothing to play for.
Cory