Cubs' Lester likely headed to injured list with hamstring injury

A stint on the 10-day injured list is all but certain for Cubs ace Jon Lester.

The left-hander injured his left hamstring running the bases during Monday's home opener, a 10-0 victory over the Pittsburgh Pirates.

Cubs manager Joe Maddon said on his WSCR radio show Tuesday that Lester would miss Sunday's scheduled start against the Los Angeles Angels at Wrigley Field and that he could miss one more after that.

"Of course he's going to miss a start," Maddon said on Laurence Holmes' show. "Coming out of the game (Monday), Jonny is going to miss at least one and probably maybe even two starts. He may. So you have to start developing Plan B. We'll start developing Plan B. We have different options."

Lester slid into second base during the second inning. He then raced home to score on Ben Zobrist's single. In the top of the third, Lester took the mound and faced two batters before exiting. The Cubs said Lester experienced left hamstring tightness and that he would undergo an MRI Tuesday. Results were not immediately announced.

Losing Lester for a long length of time would be a serious blow to the Cubs. Of the 3 quality starts put up by the rotation so far, Lester has 2.

The Cubs could turn to right-hander Tyler Chatwood to start Sunday. Chatwood, who lost his starting job last year because of poor command, opened this season in the bullpen. Left-hander Mike Montgomery went on the IL Saturday with a lat strain.

"We have to figure out how we're going to work it from there," Maddon said on his radio show. "I think Tyler Chatwood has been throwing the ball well. And again, I don't even know if the guys upstairs (the front office) have other thoughts regarding this."

Lester has been a workhorse for the Cubs since signing with them before the 2015 season. He made 32 starts in each of his first four seasons in Chicago. Last year, he was 18-6 with a 3.32 ERA.