Stars are falling left and right and baseball will be without some of its best players for several weeks.

Los Angeles' Matt Kemp, Colorado's Troy Tulowitzki, Baltimore's Nick Markakis and Boston's Dustin Pedroia are all injured with various ailments. Their recovery time could be varied from a few days to several weeks.

Matt Kemp aggravated his hamstring, which he had injured in early May. It happened just two days after he came off the DL for the same injury. The Dodgers placed him on the 15-day DL but he is expected to miss at least four weeks. Kemp, who was having an MVP-type year before the injury, will be missed. Without their best hitter, the Dodgers lost to the Brewers on Thursday, completing a four-game sweep for Milwaukee.

Tulowitzki, the Rockies' All-Star shortstop, strained his groin on Wednesday and was put on the 15-day DL. It comes at an inopportune time, as Tulowitzki had just extended his hit streak to nine games, in which he was hitting .388.

Markakis will be out 2-4 weeks with a fracture in his right wrist. The injury appeared to happen last week when he slid into a base. It was aggravated while batting during the Orioles' game on Tuesday. He will undergo surgery on Friday. It's the first time Markakis will go on the DL. He has played in at least 160 games the past three years and has never played in less than 147 games.

Second baseman Pedroia has a torn muscle in his thumb that has caused him to miss Boston's last three games. He is not on the DL yet but could be placed on it soon. The injury has made it impossible for Pedroia to swing a bat. There is a chance that he could avoid the DL by wearing a special brace to protect his hand. He has been unable to try the brace on because of swelling in his thumb.