The Blue Jays recalled Keys from Triple-A Buffalo on Tuesday.
The 23-year-old was called up for his first taste of the majors in late June and had a .467 OPS in 12 games before returning to Buffalo a month later. Manager John Schneider said last week that Keys would begin playing some left field at Buffalo, but the top prospect still seems likely to see most of his action at first or third base for the Blue Jays.