PHOENIX -- The D-backs are still trying to determine if starter Brandon Webb's right shoulder will be healthy enough for him to pitch this season.

"The priorities have shifted to making sure we know everything about his health, everything about what is causing his pain," D-backs manager A.J. Hinch said. "Up to this point, we've done everything we can to alleviate that. We thought we cleared a hurdle. His health is priority No. 1. [Webb] pitching in 2009 is a distant second until we know about him physically."

Webb had an MRI exam on his shoulder Tuesday and was evaluated by team doctor Michael Lee to determine the next course of action. The 2006 National League Cy Young Award winner has been on the disabled list since April 13, retroactive to April 7, because of the shoulder. He began to experience discomfort during Spring Training and made one start before going on the DL.

Webb, who had been following a program that concentrated on resting and strengthening the shoulder, was scheduled to make a bullpen session on Friday but felt discomfort and was sent back to Phoenix for further evaluation.

The club is uncertain if Webb will return this season but did say he will seek a second opinion. Season-ending surgery on Webb's labrum is a possibility, according to a report in the Arizona Republic.

"It's hard to say," Hinch said. "At this point, I don't think it's fair until we find out everything about the situation before we talk about this year."