Kyle Busch takes advantage of final-lap crash to win Auto Club 400 at Fontana

Luckily for Joey Logano and his fellow NASCAR drivers, they have a break next weekend to relax over Easter.

They’re going to need it.

In a finish that was wild and chaotic even by NASCAR standards, Kyle Busch swept past a crashing Logano and Denny Hamlin on the final lap Sunday to win the Auto Club 400 stock-car race in Fontana.

But the dramatics at Auto Club Speedway were just getting started.

After Busch drove under the checkered flag, Hamlin — who slammed the inside wall head-on after his collision with Logano — slumped after climbing from his car and had to be placed in an ambulance.

Almost simultaneously, Tony Stewart — irate at how Logano had blocked him on the final restart with 11 laps left — stormed over to Logano on pit road and started a shoving match that forced the drivers’ crews to pull them apart.

Stewart said Logano threw a water bottle at him “like a little girl” and that “it’s time [Logano] learns a lesson.”

And that came one week after Hamlin spun Logano in the closing laps of the race in Bristol, Tenn., prompting Logano to yell at Hamlin after that race and sparking a further war of words between them on Twitter.

Hamlin, who started the Fontana race on the pole, was taken to a nearby hospital after complaining of lower back pain and was staying there overnight for observation, his team said.

All of which nearly overshadowed the win for Busch, his first of the season and the first Cup victory at Auto Club Speedway for his team, Joe Gibbs Racing, whose other drivers include Hamlin.

“I did win the race today, by the way, that might be a story,” Busch said sarcastically.

But following the sniping at Bristol, even Busch thought he might be witness to the next chapter in the Logano-Hamlin feud as he followed behind them on the final lap.

“I did, actually,” Busch said. “Man, I’m shocked just for everything that was going on there” on the last lap. “We put on some wild races [at Fontana].”

Logano and Hamlin “were so focused on one another they left the door open,” Busch said. “Sometimes you’ve got to have a little luck on your side.”

On the final lap, Logano’s No. 22 Ford was on the inside of Hamlin’s No. 11 Toyota as they raced side by side entering the third turn. Logano kept edging right until he collided with Hamlin, sending both spinning and into the wall.

Busch, whose No. 18 Toyota had been the dominant car most of the race — he led 125 of the 200 laps — then drove past both of them on the outside.

Dale Earnhardt Jr. finished second, Logano third and Carl Edwards fourth.

Asked about the battle with Hamlin at the end, Logano was succinct: “Racing for the lead. Going for the win. That is what you’ve got to do.”

Logano, 22, spent his first four years in the Cup series with Gibbs as Hamlin’s teammate. Initially heralded as the next great NASCAR driver, Logano has only two career Cup victories, and this year he moved to Penske Racing.

On the final restart, Logano was near the lead with Stewart’s No. 14 Chevrolet behind him. When Stewart tried to pass on the inside, Logano blocked him and pinched Stewart’s car down on the apron of the track.

“I wanted to block that because I knew if [Stewart] put me three-wide that would be the end of my race and I wouldn’t win,” Logano said.

But Stewart, the outspoken three-time Cup champion and defending winner of the Fontana race, was livid with Logano, especially after some other problem on the last lap — perhaps a failing tire, Stewart said — left Stewart with a 22nd-place finish.

“He’s nothing but a little rich kid that has never had to work in his life,” Stewart said of Logano. “If he ever turns down across in front of me again, I don’t care what lap it is, he won’t make it through the other end of it.”

The next NASCAR race is April 7 on the half-mile Martinsville (Va.) Speedway.

james.peltz@latimes.com