Stewart was optioned to Triple-A Oklahoma City on Sunday, Ken Gurnick of MLB.com reports.
Stewart was battling for an Opening Day roster spot this spring, but the Dodgers ultimately opted to send him to Triple-A due to his "lack of consistency," Gurnick reports. The 26-year-old -- who posted a 3.41 ERA in 34.1 big-league innings last season -- shouldn't have to wait too long before receiving his return call to the majors, either as a spot starter or bullpen reinforcement.