He will continue to throw on the side, and the club hopes this is a minor setback. The Rangers must wait at least seven days before starting a new rehab assignment.
Webb, who won the Cy Young Award in 2006 and was an All-Star in 2007 and 2008, is attempting to return to the majors following rehabilitation from shoulder surgery. Meister cleaned Webb's shoulder of loose debris and inflamed tissue in August 2009.
After spending the last few months in Arizona working on his mechanics and building up arm strength, Webb was sent out on a rehab assignment to Double-A Frisco and made his first official start since Opening Day 2009 with the Arizona Diamondbacks. Webb had velocity and command issues, giving up five runs on eight hits in 3 1/3 innings with a fastball that was around 84 mph. He was hoping to get into a routine in which he could start every five or six days, but that won't be happening yet.
Webb, 32, signed a one-year deal worth $3 million guaranteed and another $5 million in incentives this offseason with Texas.
Richard Durrett covers the Rangers for ESPNDallas.com.