CLEVELAND -- Rangers pitcher Brandon Webb has had another setback in his attempt to come back from shoulder surgery.

Webb, who began a medical rehabilitation assignment with Double-A Frisco last Monday, felt some discomfort in his right shoulder during a bullpen session on Thursday and is being shut down again.

Dr. Keith Meister, who performed surgery on Webb in 2009, examined him Thursday and said the right-handed pitcher had more inflammation in his shoulder. Meister has prescribed anti-inflammatory medication, and Webb will be shut down for a minimum of seven days. He has been officially recalled from his rehab assignment.

Webb was the National League Cy Young Award winner in 2006 with the D-backs, and won 22 games for them in '08. But he hasn't pitched since Opening Day of '09 because of fraying and tearing in his right shoulder. Meister did a cleanup surgery on the shoulder on Aug. 3, 2009.

The Rangers signed Webb to a one-year contract in the offseason, but he is still struggling to get back to Major League form. He was on and off the mound all spring and did not pitch in a Cactus League game. He started the regular season in extended spring training and was in Arizona until last Monday, when he made his first start for Frisco. He threw 77 pitches and allowed five runs in 3 1/3 innings.