Left fielder Juan Rivera was placed on the 15-day disabled list Wednesday with what the Dodgers described as a "severe" left hamstring strain.
"It's fairly major," said Manager Don Mattingly, who was told by the medical staff that Rivera would probably be sidelined for more than two weeks.
Rivera's place on the active roster was taken by Scott Van Slyke, who was called up from triple-A Albuquerque.
Van Slyke, the son of former three-time All-Star Andy Van Slyke, is in majors for the first time. He was batting .336 with eight home runs and 25 runs batted in in 32 games in the hitter-friendly Pacific Coast League.
He made his debut in the sixth inning Wednesday as a pinch-hitter against the San Francisco Giants and drove in a run with a single to center.
Van Slyke will share time in left field with the recently-signed Bobby Abreu. Mattingly said he didn't know how playing time would be split but made clear Abreu wouldn't start every day.
"With Bobby, you run the risk of beating him up," Mattingly said.
The right-handed hitting Van Slyke will also occasionally spell the left-handed-hitting James Loney at first base.
Van Slyke, 25, was something of a late bloomer. Selected by the Dodgers in the 14th round of the 2005 draft, Van Slyke didn't hit more than five home runs in a season until his fifth year as a professional.
His breakout season came in 2009, when he hit .294 with 23 home runs and 100 RBIs for the Dodgers' high-A affiliate.
Van Slyke was the Dodgers' minor league player of the year last season when he hit .348 with 20 home runs and 92 RBIs for double-A Chattanooga.
Van Slyke arrived at the Dodgers' clubhouse shortly before the game and was issued the No. 33 jersey.
Abreu took Rivera's usual places in the lineup and on the field, batting fifth and playing left field.
Rivera was injured on Tuesday night sliding into third base on a botched sacrifice bunt attempt by Juan Uribe. He said an MRI exam he underwent on Wednesday morning revealed that in addition to pulling his hamstring, he tore a tendon in the back of his knee.
Rivera was hitting .247 and had an on-base percentage of .276. But in a lineup largely dependent on Matt Kemp and Andre Ethier, Rivera ranked third in RBIs with 13.
Utilityman Jerry Hairston Jr.'s recovery from his hamstring strain has stalled, Mattingly said. The Dodgers were concerned enough about Hairston's condition that they scheduled an MRI exam for him. If Hairston is forced to go on the disabled list, the Dodgers would probably call up infielder Justin Sellers from triple A. … Catcher A.J. Ellis threw out Nate Schierholtz attempting to steal second base in the second inning. Schierholtz was the ninth of 20 potential base stealers Ellis had thrown out to date. … Slow-starting shortstop Dee Gordon entered the game with an eight-game hitting streak.