Buehler was optioned to Triple-A Oklahoma City on Monday, Ken Gurnick of MLB.com reports.
Buehler dazzled in his Cactus League debut over the weekend, striking out five batters in a pair of scoreless innings, but he was always expected to open the year in the minors barring an injury to the Dodgers' starting rotation. The highly-regarded prospect could earn a promotion early this summer, though that will likely depend on how he does at Triple-A and the Dodgers' rotation status. He could throw 140 to 150 innings this year after being limited to 98 frames in 2017.