"It kind of grabbed me," Williams said. "I'm just trying to take a step back from it."
That leaves just two healthy starting pitchers in camp with previous experience in the Phillies' rotation: Cole Hamels and David Buchanan, who started Tuesday.
Cliff Lee's season is essentially finished, and his career could be as well, despite the fact he said he will try to rehabilitate a torn tendon in his left elbow a third time. Aaron Harang has missed two of his first three Grapefruit League starts because of back issues. He is scheduled to pitch Thursday.
The remaining healthy starters in camp include right-hander Miguel Alfredo Gonzalez, who converted to a reliever last season because of questions about his durability as a starter; left-hander Joely Rodriguez, who has never pitched above Double-A; right-hander Kevin Slowey, who is a non-roster invitee; and right-hander Paul Clemens, who is a non-roster invitee.
Right-hander Chad Billingsley could be a candidate at some point, but he is recovering from a pair of elbow surgeries and is not expected to be ready until late April.
Todd Zolecki is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.