Updated

BOSTON (Reuters) - Boston Red Sox pitcher Josh Beckett has been placed on the 15-day disabled list because of a lingering back strain, the Major League Baseball team said on Wednesday.

The twice All-Star, who last month signed a four-year contract extension worth $68 million with Boston, was forced to leave Tuesday's game against the New York Yankees after two outs in the fifth inning.

"It was a pitch to (Alex) Rodriguez that he flew out to left on," Beckett, 30, told the team's official website (http://boston.redsox.mlb.com). "My footing just slipped, and it just got tighter and tighter after that."

Beckett has been replaced in the starting rotation for Sunday's game against the Philadelphia Phillies by Tim Wakefield.

Veteran right-hander Joe Nelson, promoted from Triple-A Pawtucket, fills the opening in the team's 25-man roster.

(Writing by Mark Lamport-Stokes in Los Angeles; Editing by Ed Osmond)