TALLADEGA, Ala. — It wasn’t until the final turn of the final lap that the “big wreck” at Talladega Superspeedway finally happened Sunday.

With the chaos that claimed 25 cars still swirling behind him, Matt Kenseth won NASCAR’s Good Sam 500 in a green-white-checker finish over Jeff Gordon and Kyle Busch. And Brad Keselowski increased his Chase points lead over Jimmie Johnson with a seventh-place finish.

“I’ve gained a little bit of patience of the years,” said Kenseth, who won his second restrictor-plate race of the year (the other being the season-opening Daytona 500). “And I had to be patient two or three times (Sunday).”

Patience is always a good trait at tracks like Talladega and Daytona (Fla.) International Speedway, where races are run with restrictor plates to control speeds. The cars run in such close quarters and at such high speeds, that what’s known as the “big wreck” is always on the horizon at Talladega’s 2.66-mile track.

Sunday, it happened on Turn 4 of Lap 188 – the last of the day. Tony Stewart, leading the race on the inside lane, tried to avoid a hard-charging Michael Waltrip, who clipped Stewart’s bumper.

That sent Stewart plowing into several cars, his car flipping on its side and sliding up the track. As the massive wreck unfolded, Kenseth, who was higher on the track, slipped by untouched.

“I saw Tony’s back bumper and I saw him getting spun out,” said Kenseth. “I don’t know how that happened or how he got in that position, but I saw him spinning out and then when we were clear of him.

“I looked in the mirror and there was nobody back there, so I thought it was our race then. I just kind of slowed down and got it back to the finish.”

Gordon and Busch, who were nose-to-tail on the inside lane behind Stewart, also cleared the wreck to finish second and third. David Ragan and Regan Smith, like Busch non-Chase drivers, were fourth and fifth, respectively.

With 25 cars involved in the accident, it took NASCAR about an hour to make the results behind Kenseth, Gordon and Busch official.

Keselowski, who was involved in the wreck, finished seventh and was able to increase his lead over Johnson (another wreck victim) from five points to 14 as the Sprint Cup circuit heads to Charlotte Motor Speedway this week for Saturday’s Bank of American 500.

Keselowski’s crew chief Paul Wolfe thought Keselowski should have been scored higher than seventh.

“When it comes down to the end of the race, you score it by all means, it’s about maintaining some reasonable pace and some other things,” said Robin Pemberton, NASCAR’s vice president of competition. “Once (Wolfe) saw the video, (he) was good with it. Once we show them the evidence, everybody understands. There’s always going to be some discussion or an argument about one spot here or there, but once you talk through it, everybody understands. It’s all interpretation, when there’s a wreck of those numbers.”

Waltrip found himself in position of coming close to an unlikely victory. The owner of Michael Waltrip Racing, Waltrip was running just his fourth race of the season and was hurdling toward first place – until Stewart cut in front of him.

“It’s pretty much a buzz kill when you get crashed on the last lap and you’re not able to finish,” said Waltrip. “I can’t take it – it’s too much pressure on me as an owner and as a guy that’s the front man for the team.

Waltrip didn’t blame Stewart.

“When you don’t do this all the time, people are quick to point their fingers at you, but Tony said, ‘I’m sorry, friend, that was all on me,’ and that means a lot. I couldn’t bear causing something like that. I had my foot on the floor board for sure and I was getting pushed as hard as I could go.”

Said Stewart: “I just screwed up. I take 100 percent of the blame. It cost a lot of people a bad day because of it.”

Scott: 704-358-5889; Twitter: @davidscott14