Roush Fenway Racing's Chris Buescher drove a solid if unspectacular race on Saturday in the Ford EcoBoost 300 Xfinity Series season finale, doing just enough to make sure that nothing came between him and his first NASCAR championship. In the process, that left the door open for three Cup regulars to dominate the race and risk duelling over the day's victory.

CLICK: Full NASCAR Xfinity Series race results from Homestead-Miami Speedway.

At the end of the 200 lap race, 11th place for Buescher was indeed sufficient to see him clinch the title by 15 points over 2014 champion Chase Elliott, who had managed to finish three places ahead of Buescher in his bid to retain his crown for a second consecutive year at JR Motorsports but still fallen short in the standings.

"I was a little nervous," Buescher admitted after becoming the 26th different driver to win the second-tier championship honours, and the second from Texas after 1991 winner Bobby Labonte. "All things considered that was exactly what we needed to do and we knew that and knew we were capable of doing it. I am glad we could pull it off for all the people that were on board all year.

"I am not a points racer. I don't like it. It is not the most fun way to run the last 10 races of the season. But it is important. This is what we have been fighting for since February and Daytona and these guys have done such a great job and stuck in there with us all year and had no mechanical failures or DNFs. It is a huge accomplishment for our team."

Kyle Busch had earlier dominated the two rounds qualifying that were completed before rain forced an early end to the session. That left the grid line-up decided on the completed round and a lap of 32.116s (168.140mph) duly handed Busch his fifth Xfinity Series pole of the year and his 48th pole in 311 career starts, his second in nine races at the 1.5-mile Homestead-Miami Speedway. Joining the Joe Gibbs Racing driver on the front row was his young team mate Daniel Suarez, while row two was an all-Richard Childress Racing affair with Austin Dillon alongside Brian Scott. Buescher started from 11th, one place behind RCR's Ty Dillon and two ahead of Elliott.

Elliott's hopes of retaining his crown took an early hit when the #9 sustained damage to the left front in contact with RSS Racing's Ryan Sieg prior to the scheduled caution on lap 25 to check track conditions following earlier rain showers. Busch had led every lap up until that point, and he managed to frustrate Kyle Larson's (HScott Motorsports) attempts to take over at the front at the restart for another 30 laps.

After a long pursuit, the #42 broke through on lap 65 by which time the pair were over 15 seconds ahead of Busch's JGR team mate Erik Jones in third place. They'd even managed to put Buescher a lap down in the process. However a round of green flag pit stops and a caution on lap 116 for Josh Reaume (MBM Motorsports) hitting the wall in turn 4 came some way to bringing the field back together again on track, although Larson and Busch continued to dominate ahead of Jones, Austin Dillon and Brian Scott.

A brief shower triggered a four-lap caution but the conditions quickly improved again and soon Larson and Busch were once more fighting furiously for control of the race, both able to run the high line that few others seemed able to master. Concerns for Busch about fuel and a possible tyre were alleviated by a round of pit stops under caution for David Starr (TriStar Motorsports) hitting the wall in turn 4 on lap 174 and the stage was set for the final showdown of the season.

Larson took control of the restart but Austin Dillon seized the initiative and went to the front just as Busch was tapped by Harrison Rhodes (JD Motorsports) and hit the frontstretch wall to put the race back under caution. Frantic efforts to repair the #54 came to nought meaning Busch was out of the race with 20 laps remaining, but it was at least good news at least for Buescher who was handed the free pass and promoted back onto the lead lap in time for the last restart.

At this point the winning advantage looked to lie with Dillon who was out in front, with Penske's Ryan Blaney in second as Larson found himself tangled in a battle for third with Erik Jones. Once Larson took care of that threat he was able to quickly make his way around Blaney and set his sights on Dillon for the victory. Dillon did everything he could to repel the attack but couldn't run the high line with the same confidence, bouncing off the wall as Larson finally made his move on lap 196. Even then, Dillon did his best to get back in front of the #42, but now Larson had the upper hand and two minutes later he was crossing the finish line, claiming the chequered flag from the battered Dillon by a margin of 0.934s for his third victory in 75 NASCAR Xfinity Series races and his first since May 2014 at Charlotte Motor Speedway having led for a race-high 118 laps, although he magnanimously stepped out of the spotlight in the post-race celebrations in favour of the new series champion.

"This is championship weekend; this is all about the champions," Larson said. "Congrats to Chris Buescher. I wanted him to celebrate. It was always kind of odd when I was sitting in the stands and two cars were doing burnouts. I wanted Chris to have his moment."

Behind the lead pair, Jones and Scott finished third and fourth respectively with Blaney dropping to fifth place but still doing enough to ensure that the #22 won the car owners' championship for Roger Penske for the third consecutive time.

"I think as anyone would know, having three in a row is an amazing feat and to think we did it with four different drivers in the same car," said Penske after the race. "We fought hard to win this championship and it is interesting when you have the Cup guys drive it a few weeks and then Blaney and Alex Tagliani had a great run for us on the road courses. It is pretty special to take something home this year and that is what we were able to do here at the end of the season."

Daniel Suarez finished in sixth place ahead of Ty Dillon, and in doing so clinched the rookie of the year title, the first Mexican-born driver and the second NASCAR Drive for Diversity graduate to receive the award in a national-level series. Meanwhile the manufacturer title went to Chevrolet, the 17th time they had succeeded in clinching the honours.

Behind Dillon came Elliott, Smith and Darrell Wallace Jr. in tenth place - and then it was Buescher, last man on the lead lap but having done enough to protect his points lead coming into the season finale. "That was such an amazing race, just being careful," he said. "I was really cautious around a lot of people today.

"Our Fastenal Mustang had good speed in it, we just had to be careful out there. I can't say thank you enough to Fastenal coming on board the last race, Ford and Wiley X and Xfinity for their first year sponsoring the series and it is pretty amazing to be in this position."

"They just outran us, fair and square," said outgoing champion Elliott, who next year will be driving full time in the Sprint Cup Series in the #24 car that is being vacated by Jeff Gordon. "There's no reason to be upset about that, other than we need to do a better job and I need to be better. They just beat us."

With Buescher clinching the Xfinity title and Erik Jones having wrapped up the Camping World Truck Series title on Friday night, only one final bit of business remains before NASCAR pulls down the shutters on its 2015 season: the small matter of the Sprint Cup Series title will be decided on Sunday afternoon when one of Kevin Harvick, Jeff Gordon, Kyle Busch or Martin Truex Jr. will be crowned this year's champion.

See full race results, plus qualifying and practice speeds and full Xfinity Series championship standings.

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