The Athletics reinstated Newcomb (knee) from the 60-day injured list Tuesday.
Newcomb has been on the injured list all season due to irritation in his left knee, but he has now been given the green light to return to Oakland's bullpen after making four rehab appearances. The 30-year-old southpaw gave up two earned runs in six innings during his assignment but will likely be given low-leverage opportunities as he gets used to facing big-league hitters once again. Brady Basso was optioned to Triple-A Las Vegas in a corresponding move.