I'm assuming you are in an RT league since Small has started in RT but not TRAD - plus no one would want to use Small's TRAD stats...

Unfortunately, the game only requires relievers to get to 10 BFA (or less if there FULLY RESTED with fewer BFA). Small is 22 BFA when FULLY RESTED so he only needs to get to 10 to use him to start.

He'll get a boost of .75 recovery so 2 * 1.75 = 3.5.

To get from -2.5 to 10 he has to gain 12.5 BFA.

12.5/3.5 = 3.57 so round up and he needs 4 games of rest.

Personally I think the rules on recovery for relievers used to start are way too lenient - thus the unfortunately.

MANUAL:

Relievers who started: A reliever who started during the corresponding MLB season can be used as a starter without reduction of effectiveness (only if he starts the game with either 10 BFA or fully rested). He will be given extra BFA by the GAME at the beginning of his start, which will be taken away at the end of the game. His RECOVERY rate will be increased by 75% if his last appearance was a start.