Turner was struck by a pitch from Oakland right-hander Kendall Graveman in the first inning Monday night. Turner grunted and winced as he jogged away from the plate toward the dugout, his hand hanging limp at his side. He was quickly visited by a trainer and replaced by Donovan Solano.
Dodgers manager Dave Roberts announced the diagnosis after the game.
The 33-year-old Turner hit .322 with 21 homers and 71 RBIs last season. He also led the team and finished third in the majors by getting plunked 19 times.