TALLADEGA, Ala. — Before he was allowed in the racetrack, NASCAR made sure Tony Stewart knew the rules.

Summoned to a 6 a.m. meeting Friday morning with top series officials, the two-time champion retracted every bit of the sharp rant he launched against NASCAR while admitting he damaged the sport's credibility by likening it to professional wrestling.

"I'm sure I did hurt the integrity of it, and unfairly," he said.

Although Stewart wasn't punished for the comments he made on his weekly Sirius Satellite Radio show, NASCAR did fine him $10,000 for skipping a postrace news conference in Phoenix last week. He also was placed on probation through the end of the year.

"I can assure you, Tony Stewart knows where he stands with NASCAR right now," spokesman Jim Hunter said.