Right-hander Ryan Tepera was optioned to Triple-A Buffalo to clear a spot for Pillar, out since Aug. 6 with a sprained left thumb.
Outfielder Jose Bautista (left knee) is expected be activated off the 15-day DL as soon as he is eligible on Thursday. Manager John Gibbons said Bautista will DH often to protect his knee.
Known for making highlight reel catches, Pillar is batting .261 with seven home runs and 45 RBI. He played in 109 of Toronto's first 111 games.