Kyle Busch has been looking rejuvenated in 2013, following a lacklustre season last year that fell well below his own high standards. But despite having already found success multiple times in the Nationwide Series so far this season, a win in the Cup championship was still proving hard to come by despite three top four finishes in the first four races of this year's campaign.

In the final minutes of Sunday's race, Fontana seemed as though it would be the same 'close, but no cigar' affair all over again. After running for a grand total of 125 of the 200 laps in the lead, it looked as though Busch would be watching someone else snatch the glory at the end as his Joe Gibbs Racing team mate Denny Hamlin and Penske Racing's Joey Logano slugged it out for the race win through the final corner. But that wasn't to be the way the race went in the end after all.

Busch had started the Sunday afternoon Auto Club 400 from fourth place, although that effectively became second after Greg Biffle and Brad Keselowski had both made their way to the back of the field before the green flag as a consequence of blowing up their engines in Friday practice. That left the top three an all-JGR affair, with Hamlin on pole and the team's newest recruit Matt Kenseth a de facto third place, followed by Logano, Martin Truex Jr. and Tony Stewart.

All three JGR cars had a spell in front before the first caution on lap 30 for David Stremme spinning in turn 2. Busch picked up the lead for the restart but there was a rapid return to yellow for oil on track from Timmy Hill's car, and at the next restart Logano made a dive to the inside line and succeeded in claiming the top spot for himself.

He held the position through to the first green flag pit stops of the day on lap 68; the JGR crew did the better job and got Busch back out on front. It was a less happy cycle for Richard Childress Racing's Kevin Harvick and for Kyle's brother Kurt in the #78 Furniture Row Racing car, both of whom were cited for speeding on pit lane. A more orderly round of pit stops followed under a debris caution on lap 91 shortly after Jeff Gordon had bounced his Hendrick Motorsports #24 off the wall, and while Hamlin won the race off pit road that time it was his team mate Busch who quickly reasserted control once racing was back under way.

As the race passed the halfway point, Busch was the one putting in all the fastest laps and pulling out a gap of more than a second over Hamlin and the others. However, after another round of pit stops on lap 119 under a caution for Joe Nemechek hitting the wall in turn 2, it was Logano who won the restart tussle to lead through to the next caution on lap 130 which came thanks to Richard Petty Motorsports' Marcos Ambrose shedding debris from a blown tyre.

There was another round of pit stops, but now with under 70 laps remaining in the race it was all getting very strategic: Tony Stewart, David Ragan, Clint Bowyer, Brad Keselowski and Matt Kenseth all went for two-tyres only in their stops and duly led at the restart on lap 135, with Busch having dropped back to tenth place as the team had needed to switch to a backup battery for the #18.

Not that these setbacks proved much of a problem for Busch, who immediately hunted down those running on older rubber: 12 laps was all it took before he passed Stewart and resumed the lead again, pulling Harvick and Logano through in his wake although the latter was currently fretting about sky-rocketing temperatures in the #22.

The running order at the front stayed the same through a final round of green flag pit stops and a debris caution on lap 170 (courtesy of a second tyre blown on Ambrose's car) and after the restart there was a rapid return to yellow courtesy of a rare mishap for the veteran racer Mark Martin, who spun the #55 on the backstretch on lap 175. That brief spell of green had nonetheless mixed things up, and while Busch was still in the lead it was now Hendrick's Kasey Kahne alongside the #18 for the green flag with Tony Stewart and Joey Logano behind them.

Busch held the lead at the restart, and while the race initially stayed green while Ambrose's car finally died a smoky death and laid down oil on the track apron the yellows finally rematerialised on lap 186 when Clint Boywer spun out of tenth place in turn 3. That set up a 12-lap shootout to decide the race winner, and while Kyle Busch and Joey Logano battled for the lead at the restart it was Kurt Busch who went way down onto the apron to briefly put a nose in front before Kyle finally got the better of Logano and pushed his way back into the lead again. The question was, how long could he hold it for - especially now that the #18 seemed to be showing signs of chronic alternator ailments?

With Busch and Logano soon running dead even again, now was the time for polesitter Hamlin to return to the fray by slipping right through the middle of them. This took the air off Busch's car and he dropped back, another chance for victory apparently snatched away in the closing minutes of the race; he turned his attention instead to staying in front of Hendrick Motorsports' Dale Earnhardt Jr., who had worked himself up into fourth at just the right moment.

Up ahead, Denny Hamlin and Joey Logano were battling hard for a race win. With all their recent past feuding, what could possibly go wrong? Kyle Busch must have known he was well out of this particular battle and that it would be a miracle if it didn't all kick off before the chequered flag came out.

As the two cars battled for the lead out of turn 4 on the final lap, Logano was on the inside line while Hamlin had his nose in front on the outside line. But Logano was unable to keep the #22 down low and slid up the track, crashing both drivers into the outside wall: Hamlin's #11 ricocheted off and ran down the track into a vicious head-on impact with the concrete inside wall as well. With no impact-reduction SAFER technology on this part of the track, the car was lifted clear off the ground.

While Hamlin initially climbed out of the wrecked car, he almost immediately collapsed to the ground where he lay prone until the ambulance crew arrived. He was later airlifted to a local hospital after complaining of lower back pain. (See separate story.)

With both Hamlin and Logano out of the running, Kyle Busch deftly inherited the win and Earnhardt Jr. slipped neatly into second place as the yellow flags came out for the wreck. That froze the field, and - after an initial confusion over who had been exactly where at the split second that the caution came out - Logano was credited with third place ahead of Carl Edwards, with Kurt Busch classified in fifth place.

"I didn't think that was going to happen," said Kyle Busch of the Hamlin/Logano wreck that had handed him his first win in 31 races, the last having been at Richmond back in April 2012. "I don't know what the issue is, what the problem is. It's unfortunate for those two. I think the mentality between the two of them was, 'We're both not going to win this race because we're going to crash each other trying for ourselves,' and they gave it to the third-place guy, unfortunately.

"We had to get by before they wrecked," he added. "When they both went to the bottom side of 3 and 4, I'm like, 'Oh man, this is golden. I got enough up here I can make this happen.' Lo and behold, I put my foot to it and drove around the outside of them before they started crashing or maybe as they were crashing, I'm not sure."

Not that he was allowing the controversial circumstances to spoil the feel-good moment of his long-awaited return to Sprint Cup victory lane.

"I was in the right place at the right time," he said. "Feels so good to finally win. We weren't going to win if it wasn't for those two battling. If they would have been single file and just racing, it would have went down in order," he admitted.

Busch dedicated the win to team owner Joe Gibbs and also to engine suppliers Toyota Racing Development, about whom he's been critical in the past over reliability but who more than proved themselves at Fontana, a circuit just down the road from their US corporate headquarters.

"Can't say enough about all of Joe Gibbs Racing, everybody at TRD - we appreciate their support of course.," he said. "Finally we get the 'home' win for Toyota, finally we get a win for Joe. Joe, this one's for you buddy. I drove my butt off right there at the end. You know, what I always do!"

Dale Earnhardt Jr. was also happy with the outcome, as second place at Fontana propels him into a 12 point lead in the NASCAR Sprint Cup Series championship standings over Brad Keselowski - making 2013 officially his best start in the title battle that he's had in his Cup career.

"We were lucky there at the end and came in and got some fresh tires and that sort of fixed our mistakes and helped us to get a good finish," said the firm fan favourite. "We had a good car and had some wheel issues, but was real happy about how we finished and made it up. We had a good enough car to run there, and were happy to get the finish."

The initial timing results had put Kyle's older brother Kurt in third place, until a post-race review of exactly who had been where when the final caution came out put him down to fifth place. Even so, that's an impressive result for Busch and Furniture Row Racing, which is far from one of the traditional top Cup teams but one that has been growing in confidence since taking a chance on the controversial former Cup champion.

"We had to overcome a number of issues," Kurt explained afterwards. "This week it was getting into someone else's oil before slapping the fence and then being penalised for speeding on pit road. Though we never quit, and do the best we can to fight back, it sure would be nice to have a smooth race, something we haven't had this year!"

Kurt had even briefly taken the lead from his kid brother at the restart. "I had a chance to pass him for the lead on that final restart, and I took it," he confirmed. "Normally I'd have followed him, pushed him and drafted with him and tried to break away from the field.

"But I went to his outside, and it was a move that held him up, took his momentum away and gave me a shot for clean air," he continued. "The car just was a little tight on that top-side, couldn't quite get the power down and couldn't get in front of him and Logano to seal the deal.They were fast, and that was my one shot to win."

It's certainly a strong finish for the Busch brothers to the first five races of the Sprint Cup season, which now has a brief hiatus for the Easter break before resuming with the Goody's Fast Relief 500 at Martinsville on April 7.

Full Auto Club 400 race results. Post-race Q&A with winner Kyle Busch