It was only a matter of time.  Despite his early success, Red Sox pitcher Bartolo Colon has found himself in a familiar place - the disabled list.

The culprit this time around is a sore back. Colon suffered the injury with a series of hard swings-and-misses at Cole Hamels pitches in Monday’s 8-2 loss at Citizens Bank Park. He was removed after only four innings in his second loss of the season.

"He's had a history of issues, that's why we're being cautious," manager Terry Francona told the Boston Herald. "One thing leads to another. We explained that to him, and he understood. We'll just let things cool down and get him back out there."

Colon's injury means that rookie Justin Masterson likely will maintain his spot in the rotation. Expect Colon to be out until at the least the All-Star break and maybe longer.

Francona said Daisuke Matsuzaka was set to start Saturday against St. Louis. Matsuzaka (8-0, 2.53 ERA) allowed two runs and three hits over five innings in a rehab start for Triple-A Pawtucket on Monday night, his first game action since straining his rotator cuff last month.