Darlington, S.C. ? If Mark Martin keeps winning like this, even he might have to concede that he’s racing for a Sprint Cup championship.

The 50-year-old Martin won for the second time in the last four races, outlasting Jimmie Johnson in a wreck-filled show at Darlington Raceway on Saturday night.

“Once we got out front, man, it was just easy. The car was awesome,” Martin said.

Martin’s only other Darlington win was in 1993 Southern 500, a 16-year stretch.

Martin’s victory ended a long, hot day for NASCAR that began with the sobering news of Jeremy Mayfield’s failed drug test and indefinite suspension, which was announced about two hours before the start of the race.

The garage buzzed most of the afternoon about who was snagged by NASCAR’s beefed up testing system.

“I don’t know much about it,” Johnson said. “There’s a policy in place, and it’s there for a reason.”

Martin considered driving away for good a few years ago but re-upped with Hendrick Motorsports for 2010 earlier this week.

On Friday, Martin was adamant the extra year wasn’t about seeking a title, simply manifesting the joy he feels these days each time he steps on the gas.

And Martin’s doing it as well as he ever has.

“Hey, man, I’m loving it,” Martin said.

He ended a 97-race winless streak in Phoenix last month and proved there’s no age limit on mastering the track “Too Tough To Tame.”

Martin led the final 46 laps in his 37th career Sprint Cup victory.

Besides his two wins Darlington wins in NASCAR’s top series, Martin has won a record eight Nationwide Series races the track.

This time, Martin had to show as much patience as speed, handling a record 17 cautions on Darlington’s 2-year-old pavement.

The wrecks surpassed the previous high of 15 set in Darlington’s spring race 14 years ago, and more than doubled the eight of last year after the track was freshly paved.

Johnson wrecked in qualifying and had to start 42nd. He made it all the way to Martin’s bumper before settling for second.

“This is one of the most difficult places we run,” said Tony Stewart, who finished third.

Ryan Newman, Stewart’s teammate, was fourth, followed by points leader Jeff Gordon. Brad Keselowski, in seventh, gave Hendrick four cars in the top seven.

One by one, the slick surface knocked out the top contenders.

Kyle Busch, the defending race champ and last week’s Richmond winner, saw his chance to repeat disappear when he slammed the wall on lap 274.

Busch lost the Nationwide race Friday night when a tire went flat while waiting for a green-white-checkered finish. This time, Busch drove his Toyota into the garage and did not return.