Jimmie Johnson and Brad Keselowski were nearing the start-finish line after a late restart at Texas when their cars suddenly slammed together.
Somehow, they managed to maintain control and prolong their battle for the NASCAR Sprint Cup championship.
''Fortunately, we both stayed 1-2 and didn't crash, didn't lose a spot on the racetrack,'' Johnson said. ''But I knew he was serious about the race lead prior to that and that took it to a new level. `'
Johnson still has the advantage, holding a seven-point lead with two races left after winning Sunday. But the five-time champion knows he's got a fight on his hands from the young challenger who is trying to get Roger Penske his first Sprint Cup title.
''The gloves are off and it's bare-knuckle fighting,'' Johnson said.
Before their big bang inside the final 10 laps, Keselowski was coming up the track with Johnson on the outside. After the No. 48 Hendrick Motorsports Chevrolet got loose, Johnson seemed to be charging ahead before they ricocheted off each other heading toward the frontstretch. They stayed side-by-side into the next lap, and appeared to scrape each other again - and still had to get through another restart.
''I raced hard, and I'm sure someone would say dirty,'' said Keselowski, who overcame an early pit problem and got back up front by taking only two tires on one of the last stops. ''Anytime you run close to certain guys you're racing them dirty according to some people. But I raced hard, and we both came back around, so there's something to be said for that.''
When there was a third restart in the last 20 laps, for a green-white-checkered finish, Johnson regained the lead for the seventh and last time to win from the pole for the second week in a row. He charged on the outside after some more bumping, clearing Keselowski on the backstretch with 1 1/2 laps left.
But only after a little finger-pointing at Keselowski, who after his runner-up finish went to Victory Lane to shake the winner's hand.
''Just wanted him to use his head. There is no sense in taking us both out in the process,'' Johnson said. ''That's the first time that we've really engaged at that level and raced each other that hard. To his credit, he did a nice job of getting right to the edge, and we brought home race cars. We weren't wadded up to look like a bunch of fools.''
They go to Phoenix next week, where Johnson has won four times and finished fourth eight months ago in the second race of the season. Keselowski finished fifth then and has never won there.
The season finale is at Homestead.
Johnson led 168 of the 335 laps at the 1 1/2-mile high-banked track for his 60th career victory and the 700th in Sprint Cup for Chevrolet.
It also means a sizable donation for disaster relief on the East Coast in the wake of Superstorm Sandy. Lowe's, Johnson's primary sponsor, had pledged to match what he earned at Texas - $492,086.
Keselowski had never finished better than 14th at Texas before leading five times for 75 laps.
He fell from first to ninth during a stop when he slid too deep into his stall and got caught in a jam of cars on pit road after his team had to push him backward. On the next stop, after working his way back to fourth, Keselowski opted for only left-side tires on his No. 2 Dodge when everybody else took four tires.
After restarting the final 20 laps in first again, the strategy almost worked. Until the last restart.
Kyle Busch, who led four times for 80 laps, finished third with a close-up view of Johnson and Keselowski.
''Those guys got side by side and they were running hard. It seemed like Brad was moving up the racetrack to force Jimmie into the dirty racetrack. ... He's no dummy. He's smart,'' Busch said. ''Last restart though, Jimmie got an excellent restart.''
There were nine cautions for 49 laps, including that late flurry that changed the race. It sure didn't start that way, before some yellow flags in bunches.
After the April race at Texas ended with a track-record 234 consecutive green-flag laps, the first 100 laps Sunday were without a caution. Those 334 laps were the equivalent of 501 miles, or a full Sprint Cup race at Texas.
Before all the cautions, Johnson set the pace and quickly was back in front of the field after the first two green-flag stops. Then there were three cautions in a 20-lap span.
Tony Stewart finished fifth, followed by Clint Bowyer, who is 36 points back in third in the series standings.
Keselowski feels like he controls his own destiny. But Johnson is in the lead.
''It's a small amount of control, but we're definitely in control. We don't have to catch any or make up any points,'' Johnson said. ''Seven points is nothing to feel comfortable about and to relax on. We're still going to go into Phoenix and act as if we're behind and go in there to try to sit on the pole and win the race again.''