Larson, who led the most laps in Sunday’s race at Phoenix Raceway, had fallen out of lead late but a caution for a broken brake rotor on the track on Lap 283 of 312 sent all the lead-lap cars down pit road for new tires.
Larson, who had won the pole on Saturday and had the first pit stall, just edged Denny Hamlin off pit road – picking up three spots and moving into the lead when the race restarted on Lap 289.
For the final 23 laps, Larson deftly held off a determined Martin Truex Jr. and took the checkered flag by 0.398 seconds to win his career-best 10th win of the 2021 season.
“I can’t – I cannot believe it. I didn’t even think I’d be racing a Cup car a year and a half ago,” Larson said. “To win a championship is crazy. I’ve got to say first off thank you so much to Rick Hendrick, Hendrickcars.com, Jeff Gordon, NASCAR, every single one of my supporters in the stands, watching at home, my family. I’ve got so many of my friends and family here.
“There were so many points in this race where I did not think we were going to win. Without my pit crew on that last stop, we would not be standing right here. They are the true winners of this race. They are true champions.
“I’m just blessed to be a part of this group. Every single man or person, man and woman at Hendrick Motorsports, this win is for all of us, and every one of you. This is unbelievable. I’m speechless.”
Larson, 28, was indefinitely suspended from NASCAR and fired from Chip Ganassi Racing in March 2020 for using a racial slur over the radio during a public iRacing event.
He sat out the remainder of the 2020 season, with a return to NASCAR never a certainty. After fulfilling the requirements by NASCAR to lift his suspension, Hendrick Motorsports opted to add Larson to its four-driver Cup team for the 2021 season.
Larson and his No. 5 Chevrolet team quickly showed they would be a factor for the championship this season, winning the season’s fourth race at Las Vegas Motor Speedway.
He won the regular season title and four races in the playoffs that helped him advance to the Championship 4 and a chance Sunday to win his first NASCAR title.
Larson said as he drove around the track after taking the checkered flag, he had tears welling in his eyes.
“The crowd was cheering loud, and it was just a different atmosphere than I’ve ever been a part of,” he said. “This event was crazy. This format is wild. I’m glad we were able to get it done.
“A big shout-out to my parents for getting me involved in racing, my dad for everything he did, building my go-karts when I was young to get me playing around, my mom for videotaping every lap I ever raced and giving me something I could look at and study and get better.
“Gosh, so cool, I cannot believe it.”
Hamlin finished third in the race and the championship standings, Ryan Blaney was fourth and 2020 champion Chase Elliott finished fifth and fourth in the final series standings.
Rounding out the top-10 in the race were Aric Almirola, Kyle Busch, Kevin Harvick, Christopher Bell and Brad Keselowski.
Following the break between Stages 2 and 3, the lead-lap cars all pit with Larson the first off pit road.
When the race resumed on Lap 198, Larson was followed by Elliott, Hamlin, Truex and Kyle Busch.
With 85 laps remaining in the race, Larson led by about a second over Elliott, followed by Hamlin, Truex and Harvick.
On Lap 236, Elliott was able to close to Larson’s rear bumper, dropped to his inside, and came away with the lead again.
On Lap 244, Hamlin got around Larson to take over the runner-up spot behind Elliott.
Just as Truex hit pit road to kick off a round of green-flag pit stops, Anthony Alfredo wrecked hard off Turn 2 following a tire failure to bring out a caution.
The remaining cars elected to pit with Hamlin the first off pit road. When the race returned to green on Lap 255, Truex inherited the lead by staying out. He was followed by Blaney, Hamlin, Elliott, Logano and Larson.
With 40 laps to go, Truex maintained about a 1-second lead over Hamlin as Elliott remained in third.
David Starr dropped a brake rotor on the track in Turn 3 which forced NASCAR to throw a caution for debris. The lead-lap cars all elected to pit with Larson the first off pit road.
On the restart on Lap 289, Larson was followed by Hamlin, Truex and Elliott.
With 20 laps to go, Larson maintained a small lead over Truex as Elliott battled Hamlin for third.
Elliott finally got around Hamlin with 15 laps remaining and began closing on Larson and Truex.
With 10 to go, Hamlin worked his way back around Elliott to reclaim the third spot.
Larson held off his Hendrick teammate and fellow championship contender, Elliott, by 1.062 seconds to win Stage 2.
Hamlin finished third, Truex fourth and Blaney rounded out the top-five.
Following the break between Stages 1 and 2, all the lead-lap cars pit with Elliott the first off pit road.
On the restart on Lap 84, Elliott was followed by Truex, Harvick and Hamlin.
With 80 laps remaining in the second stage, Elliott’s lead over Truex hovered around 1.3 seconds as Harvick ran third.
Truex patiently ran down Elliott and cleared him for the lead again on Lap 120.
On Lap 129, Quin Houff wrecked entering Turn 3 after a tire failure to bring out a caution. All the lead-lap cars elected to pit with Elliot the first off pit road.
Kurt Busch, Starr and B.J. McLeod were all penalized for speeding on pit road and had to restart from the rear of the field.
Elliott led the way on the restart on Lap 136 followed by Harvick, Larson and Truex. Hamlin lined up ninth.
On Lap 140, Ricky Stenhouse Jr. wrecked off Turn 3 after a left-front tire failure to bring out the fifth caution of the race.
Elliott remained out front when the race returned to green on Lap 146. He was followed by Larson, Harvick and Truex.
Chase Briscoe got hit by Kyle Busch, had a left-rear tire go down and Briscoe hit the Turn 3 wall.
Most of the lead-lap cars all pit with Larson the first off pit road. Almirola was penalized for speeding on pit road and had to restart from the rear of the field.
When the race returned to green on Lap 162, Tyler Reddick – among those who stayed out – led the way. He was followed by Kurt Busch, Alex Bowman, Daniel Suarez and Larson.
Larson used a three-wide move on the restart to quickly power into the lead as Elliott following him into second.
With five laps remaining in the second stage, Larson maintained about a half-second lead over Elliott with Hamlin in third.
Truex grabbed the lead late and cruised to the Stage 1 victory over Harvick.
Elliott finished third, Hamlin was fourth and Larson rounded out the top-five.
Larson started on the pole and led the first lap but Elliott went to his inside to move into the top spot on Lap 2.
On Lap 7, Corey LaJoie got into Bubba Wallace the contact sent Wallace into the Turn 4 wall to bring out a caution. The damage was severe enough to bring an early end to Wallace’s race.
Larson elected to pit under the caution for tire and fuel. Elliott remained on the track and in the lead when the race returned to green on Lap 12. Larson restarted 31st.
On Lap 15, LaJoie got into Stenhouse and both spun and wrecked in Turn 3 to bring the caution back out.
Most of the lead-lap car elected to pit with Elliott the first off pit road. Bell was among those who stayed out and inherited the lead.
On the restart on Lap 21, Bell was followed by Blaney, Keselowski and Ross Chastain. Larson lined up fifth.
With 30 laps remaining in the first stage, Blaney held a small lead over Harvick with Elliott in third and the top championship contender.
On Lap 49, Harvick went to the inside of Blaney and took over the lead for the first time in the race.
Blaney battled back to lead Lap 50 only to see Truex power from third to move into the lead on Lap 51.
With 15 laps to go, Truex had built a 1.7-second lead over Harvick as Elliott remained in third.