Webb initially was going to throw to hitters Sunday or Monday, but that session was pushed back a couple of days. Manager A.J. Hinch said Webb might throw a bullpen session next instead of live batting practice, but did not set a date.
"He's not feeling bad, but he's not feeling strong," Hinch said. "It's not necessarily that unexpected. He is seven months post-surgery and these things get a little testy from time to time."
Webb, coming off shoulder surgery in August, was unavailable for comment before the Diamondbacks faced the Colorado Rockies in a split-squad game. But the 2006 NL Cy Young Award winner sent word through a team spokesman that he felt fine after playing catch.
Hinch has said Webb could pitch in his first spring game around the middle of the month. But Webb, who made only one start in 2009, likely will need to throw at least a couple more times before making his first start.
"He's not having trouble being on the mound," Hinch said. "He's not having trouble every time he throws a baseball like he did last season. He's in a little bit of a dead period in his rehab program that we're trying to get him past before we move him on."
Hinch said the Diamondbacks could have Webb throw another bullpen session instead of batting practice to make sure he is comfortable before he increases the intensity by facing hitters.
Webb last threw a bullpen session on Thursday and called it "stagnant" and "average."