Clash between Kyle Busch, Carl Edwards simmers ahead of NASCAR’s Auto Club 400 in Fontana

The always aggressive Kyle Busch has had his fair share of feuds with other NASCAR drivers in his six-year career, but Busch did his best Friday to sidestep a new one with Carl Edwards.

As he waited for Auto Club Speedway to dry after a night and morning of rain in Southern California, Busch said he was less concerned with Edwards than with winning Sunday’s Auto Club 400 in Fontana, the Cup series’ fifth race of the season.

Then, when the track was deemed dry enough for the drivers’ first practice, Busch promptly hit an undetected wet spot and lost control of his No. 18 Joe Gibbs Racing Toyota. His car slammed into the turn-four wall, then plowed through the drenched infield grass in front of pit road.

“You just skip right across [the wet spot] real quick, and you think it’s OK. And then you go [back] to the throttle, and the thing spins out,” Busch said.

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Busch, 25, went to a back-up car and qualified eighth for Sunday’s race, while Juan Pablo Montoya won the pole position with a lap of 184.653 mph. Busch’s teammate Denny Hamlin qualified second at 184.270.

Defending race winner and reigning Cup champion Jimmie Johnson qualified 16th, Edwards was 18th and Dale Earnhardt Jr. starts 30th in the 43-car field.

Busch got on Edwards’ bad side in the season’s second race, in Phoenix last month, when Busch abruptly veered his car into Edwards’ Ford, which had started on the pole. Busch finished second; Edwards’ damaged car finished 28th.

Despite a post-race apology from Busch, Edwards hasn’t let it go. After Busch edged Edwards to win Sunday in Bristol, Tenn. — and after Edwards might have tried to shove Busch’s car out of the lead in retaliation but didn’t — Edwards said Busch still had payback coming.

“If Carl wants to continue saying that he still owes me one, whatever. I don’t care,” Busch said. “I’m racing my race and … racing all of my competitors and not worrying about all of that stuff.”

Edwards, who won this month in Las Vegas, conceded he “was kind of a little bit whiny” after Bristol because he “was just so frustrated” at not winning the race. Edwards also said, “I wouldn’t call it a rivalry [with Busch] right now, but it is just hard racing.”

Yet Edwards, 31, also acknowledged that his payback threat might be advantageous.

“I can tell by the way [Busch] drove his car on those restarts [at Bristol] that he knew I was there and he was worried about me,” Edwards said. “That is good. You want a guy to be in that position.”

Busch said Edwards did bump him once in the closing stages at Bristol but not enough to spin out Busch’s car. “We raced each other hard; we raced each other clean,” Busch said.

“It is nothing personal,” said Edwards, who drives for Roush Fenway Racing. “That deal at Phoenix cost me 28 points at least, in my opinion. I told him I owed him one, and he asked for me to give it back to him at the All-Star Race [in May]. You never know. Maybe that is how it will go.”

Busch’s older brother, Kurt Busch, leads the early Cup standings by a single point over Edwards. Kyle Busch is sixth in the standings, 17 points back.

Johnson, meanwhile, is seventh in points — 20 points behind Busch — and has yet to win this season as he pursues an unprecedented sixth consecutive championship. Johnson also holds the record for most wins, five, at Auto Club Speedway.

His No. 48 team is running “in good shape” but “if we leave here with a poor run” then “we know we have a lot of work to do,” Johnson said.

james.peltz@latimes.com