LOS ANGELES—Dodgers pitcher Clayton Kershaw returned to the injured list Saturday, days before Los Angeles begins a postseason defense of its World Series championship. The three-time Cy Young Award winner has left forearm discomfort, the same injury that sidelined him for 57 games from Aug. 9 to Sept. 13. Kershaw left his start Friday night against Milwaukee after 1 2/3 innings. He gave up three runs with one strikeout. He is 10-8 with a 3.38 ERA, his highest mark since a 4.26 ERA as a rookie in 2008. “Chances are, it’s not looking great for October right now,” a glum Kershaw said. “I just wanted to be a part of this team going through October. This team is special.” The Dodgers went into Saturday two games behind San Francisco in the chase for the NL West title but were assured of hosting the NL wild-card game if they don’t catch …