Twice, A.J. Burnett felt pain from his groin Sunday morning while he threw a bullpen session. It did not linger. The 37-year-old righthander said everything went "better than expected."

Still, he harbors fears of a larger problem, and that is why Burnett will see a doctor Monday. His Wednesday start against Atlanta is still in question.

"I feel good," Burnett said, "but I want my mind to be 100 percent."

The Phillies were concerned enough to limit David Buchanan's start Sunday at triple-A Lehigh Valley to 12 pitches in one inning. The Phillies have not listed a starter for Wednesday. Manager Ryne Sandberg said Buchanan was held back as a precaution.

Burnett will undergo an ultrasound examination Monday. He spent time on the disabled list over the last two seasons with a torn right calf and a broken orbital bone near his right eye.

"I just hope it's not a [sports] hernia or something like that," Burnett said. "That's what I'm worried about. Tomorrow will give me peace of mind. As far as physically, it was a good day today. A lot better."

Burnett walked six batters in two straight starts. He last had a streak like that in 1999 as a 22-year-old rookie pitcher for the Florida Marlins. The groin problem, he said, contributed to his recent erratic control, although Burnett was shaky during spring training, too.

On Sunday morning, he engaged pitching coach Bob McClure and bullpen coach Rod Nichols in a lengthy discussion after throwing. They practiced mechanics.

"I feel good enough to throw," Burnett said. The Phillies hope that statement remains true later in the week.

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