Chastain took the field three-wide on a restart with 16 laps to go to move into the lead but Logano – among a group of cars that pitted for new tyres during the previous caution period – was coming up fast through the field.
Logano finally caught Chastain with two laps to go and easily made his way around him to reclaim the lead and held on by 0.817 seconds for the victory.
Logano’s victory sees him automatically advance to the championship 4 at Phoenix and will compete for the 2022 series title regardless of how he finishes in the next two races – next weekend at Homestead and then at Martinsville.
The win could prove a good omen for Logano because the driver who has won the first race of the semi-final round of the playoffs has gone on to win the championship in three of the last four seasons.
Earlier in the race a flashpoint erupted between Wallace and Larson when the pair tangled and the incident spilled over into the infield.
On lap 95 Larson slid up into Wallace and knocked him into the outside wall. As Wallace came back down the track, he slammed into the right-rear of Larson’s Chevrolet, sending both cars spinning, with the crash also took out playoff contender Christopher Bell.
After exiting his car, Wallace walked over to Larson’s wrecked car and started shoving Larson.
“We had a super-fast car – not on short run speed, we were kind of falling back there and Larson wanted to make it a three-wide dive bomb,” Wallace said. “He never cleared me. I don’t lift. I know I’m kind of new to running up front, but I don’t lift.
“I wasn’t even in a spot to lift, he never lifted either and now we are junk. Piss poor move on his execution.”
Bell was arguably the biggest loser in the clash as he is now in danger of elimination from the playoffs with two races of the semi-finals to go, as defending NASCAR Cup champion Larson was already eliminated from the playoffs in the previous round.
Kyle Busch finished third as Chase Briscoe rebounded from dropping a lap down to finish fourth ahead of Denny Hamlin who rounded out the top five.
With two races remaining in the latest round of the playoffs, the four drivers lowest in points and under threat of elimination are Bell, Briscoe, William Byron and Ryan Blaney – Blaney was also caught up in a crash during the Las Vegas race.
NASCAR Cup Las Vegas – Race Results