Johnson qualified first and was fastest in all three practice sessions en route to winning the NASCAR Banking 500 at Lowe's Motor Speedway. It was the first "perfect weekend" (a goal set by crew chief Chad Knaus) of the three-time champion's 286-race career, though some took issues with the criteria.

"You have to lead every lap for it to be a perfect weekend, so he still doesn't have it," runner-up Matt Kenseth said, laughing.

Semantics might be the only way to stop Johnson's march through the NASCAR record books. After Johnson stretched to a 90-point lead on Mark Martin at the midpoint of the Chase for the Sprint Cup, his next stop is Martinsville Speedway, where the No. 48 Chevrolet has won five of the last six races and he holds an average finish of 5.3 (best among active drivers).

Johnson, who tied Buck Baker for 13th on the all-time list with his 46th career victory, has won the last two races and three of the first five in the Chase. Dating to 2007, he has won 10 of the last 20 races in the 10-race title run, which has ended the season since 2004. Yet the Hendrick Motorsports driver resists the notion the championship is his to lose.

"We're only halfway through," he said. "So much can happen. If we don't have problems, I feel we've got a very good chance to win the championship. But the unknowns we can't control."

Johnson, though, has been impervious to Chase misfortune since his first championship. It's been more than three years since he failed to finish a Chase race: 31 consecutive top-15 finishes.

"Those guys are awesome," Kenseth said. "Whenever it's crunch time, they do this."

Johnson's two chief challengers before Saturday faltered. Juan Pablo Montoya (35th), who had notched a record four consecutive top-five finishes to start the Chase, fell three spots to sixth in the standings after damage suffered on a restart incident with Clint Bowyer and Martin, whose battered Chevy limped home 17th after starting second.

Jeff Gordon (fourth) improved two spots to third in the standings but still lost 30 points to his Hendrick teammate. "You give them momentum like this, they are only going to get stronger," Gordon, who trails by 135 points, said of Johnson.

The last hope for a stumble by Johnson might be Nov. 1 at Talladega Superspeedway. The 2.66-mile oval known for multi-car pileups is Johnson's third-worst track in average finishes (17.7).

"There's a lot of danger out there," Johnson said. "We all know the risks at Talladega. I'm very, very happy where we're at, but there's a lot of racing left."

Enlarge By Terry Renna, AP Jimmie Johnson raises the trophy after winning the NASCAR Banking 500 Sprint Cup Series race at Lowe's Motor Speedway in Concord, N.C., Saturday.