Craig Kimbrel to miss 3-6 weeks after knee surgery

— -- Boston Red Sox closer Craig Kimbrel will have surgery Monday to repair cartilage in his left knee and is expected to miss 3-6 weeks.

The Red Sox announced Saturday that Kimbrel has a medial meniscus tear and has been placed on the 15-day disabled list.

Kimbrel was unavailable Friday night for the ninth inning of a 6-5 victory over the Tampa Bay Rays after tweaking his left knee during pregame warm-ups, according to Red Sox manager John Farrell.

In search of bullpen help, the Red Sox on Saturday acquired side-arming right-hander Brad Ziegler from the Arizona Diamondbacks for two minor leaguers.

Farrell told reporters that Ziegler and Koji Uehara will both get save opportunities while Kimbrel is out. Ziegler is still traveling to Boston and will not be available for Saturday's game against the Rays, Farrell said.

Kimbrel, who has a 3.55 ERA and 17 saves in 34 appearances, was among six Red Sox players named to the American League All-Star team. Ziegler has a 2.82 ERA and 18 saves in 36 appearances.

The Red Sox made a series of other roster moves Saturday, recalling pitcher Noe Ramirez from Triple-A Pawtucket and adding infielder Michael Martinez, who also was acquired in a trade Friday, to their active roster.

Infielder Marco Hernandez was optioned to Pawtucket.

Information from ESPN staff writer Scott Lauber contributed to this report.