For more than four seasons, motorcycle star Ricky Carmichael's biggest adversary has been the record book. At Budds Creek Motocross Park in rural St. Mary's County on Sunday, Carmichael got the better of that foe yet again, further cementing his place in racing history with his unprecedented 100th career victory.

Carmichael dominated both 250cc motos, or heats, becoming the first rider in the American Motorcyclist Association's 80-year history to reach the century mark in event victories, which are determined by the best total placement in two motos.

The 24-year-old Carmichael -- winner of four consecutive 250cc series championships -- stopped at the finish line, raised his arms three times and then took a slow victory lap in front of an appreciative, sun-splashed crowd of 16,433.

"It's unreal, I tell you; I sit up here today and I don't even feel like I've ridden 100 races," Carmichael said during a raucous victory celebration that included father Rick Carmichael and grandfather Hugh Carmichael. "One hundred wins -- I have nothing left to prove."

Yet, as Carmichael later hinted, his quest is far from finished. Potential successor James "Bubba" Stewart, an 18-year-old fellow Floridian, appears poised to challenge Carmichael in next year's indoor supercross season and outdoor 250cc motocross campaign.

"If anybody's going to beat [the record], he's going to be the guy," Carmichael said after Stewart thoroughly whipped the field in yesterday's two 125cc motos. The sport's first African American superstar won the first race by 37 seconds and the second by more than a minute. The feat was made more impressive by a pair of "horrible starts," in Stewart's words, which he twice erased with blistering haste.

"I like looking back and not seeing anyone," explained Stewart, who was serenaded with screams of "Yeah, Bubba" and "Way to go, Bubba" all afternoon.

Since returning from a shoulder injury last June at this same racetrack, Stewart, a telegenic fan favorite, has won an astounding 22 consecutive motos and 11 events. His 21 event wins have him tied for 20th all-time.

But today's event was about Carmichael, who, as Stewart observed, has gone from pancakes to protein bars as his career progressed. The 5-foot-8, 150-pound fitness freak has won motocross championships seven straight summers. He also achieved the sport's ultimate feat two summers ago, becoming the first rider to win every moto in a single season.

Last fall, he ripped up the anterior cruciate ligament in his left knee, sidelining him for the entire supercross series. He said the time off rejuvenated him, and entering Sunday's race he had won the first six motos of the season.

The streak continued on a brilliant day for racing here in Budds Creek, a small town about 15 miles southeast of La Plata on the western edge of St. Mary's County. The same sun that baked the infield masses turned segments of the hilly clay course from loamy brown to a dustier shade of tan.

Carmichael had one brief scare during the first moto, stalling out after an awkward turn, but he recovered to win by more than six seconds. He easily led the second moto from wire to wire, prompting crew members to don commemorative T-shirts, sponsors to hand out commemorative plaques, and rivals to offer their own words of praise.

"I don't even know how many [wins] I have, but it's not even close," said second-place finisher Chad Reed, a popular Australian. "I know the hard work it takes to win one, let alone 100."

"That's unbelievable," added Frenchman David Vuillemin, who was third overall. "It's good to be racing at the same time as a guy like Ricky."

Carmichael repeatedly expressed disbelief about his accomplishment, and said the magnitude of 100 wins cycled through his head while he was on the track.

"You almost have to sit back and chuckle at it, because it's almost unbelievable," he said. "It's a lot of laughs, a lot of sweat, a lot of [angry] moments -- but everything has worked out great."

Next year, Carmichael will race for Suzuki under a contract that will last a maximum of three years, at which point he says he will retire. But Erik Kehoe -- his team manager with Honda -- predicted that the record book will continue to be battered.

"He's breaking records right now that I think are gonna stand for a long, long time," Kehoe said. "He's still got a couple years, and there's a lot of wins left in him."

James "Bubba" Stewart, 18, has 21 event wins -- 79 wins behind Ricky Carmichael.