"I feel better that I'm able to get my work in," Richard said. "But we don't want this thing to go the other way."
Richard has been troubled for nearly three weeks by an intestinal virus that caused him to miss a start in San Francisco on April 20 and then dogged him in three starts he made thereafter, when he went 0-3 with a 13.09 ERA.
Richard has had medical tests done this week as the team goes about trying to find answers for what is ailing him, and why he hasn't been able to kick the virus by now, one that initially caused him to lose 12 pounds.
"[The doctors] think there's an underlying issue in my digestive tract," Richard said.
Richard is scheduled to have a colonoscopy on Friday in San Diego, though he'll join the team during its three-game series against the Rays that starts that same day in Florida.
"He will throw over the weekend and we'll determine where he's at physically," said Padres manager Bud Black.
Corey Brock is a reporter for MLB.com. Keep track of @FollowThePadres on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.