10:15 AM ET

The speculation about Truex's future in NASCAR was over in seven words.

"I'm back in the 19 next year," Truex said at Nashville Superspeedway before his statement was even more brief.

As he pondered his future over the past several months, the NASCAR champion was succinct and nice. The most Truex would reveal was that the organization needed a decision from the driver this summer.

"The competitive side of me said I'm not done and I'm going to keep fighting, so here we are," Truex said.

Next year will be his 18th in the Cup Series, and he has 31 career wins and two titles. He heads into the race at Nashville winless on the season, but ranked sixth in the points.

JGR can now focus on two-time champion Kyle Busch after Truex's signing. Mars, Inc. is leaving NASCAR after this season in order to sponsor the No. 18.

JGR is still a title contender with Truex back. In four of the past five seasons, he advanced to NASCAR's title-deciding championship race, and in the last one, he won the title. He has finished second in the championship three times.

Since joining JGR, Truex has won 16 times.

David Wilson, president of Toyota Racing Development, said they were delighted that the Cup champion was back in his Camry TRD for at least another year.

It was not clear what Truex would do because of his struggles in the new Next Gen stock car. Christopher Bell, Kyle Busch, Denny Hamlin and Martin Truex have three victories each. They haven't reached Victory Lane.

The good teams will be the good teams everywhere, according to Busch. It is patchy right now with just getting an understanding of this car.

The struggles in performance bothered Truex.

Truex doesn't like not running well. I want to win. Everybody is working hard right now. It's a sport that can go either way. I have been worse off before. We're in a good spot and we'll keep doing everything we can.