Hendrick Motorsports driver William Byron took the lead on a restart with six laps remaining and held off the field to claim Sunday’s AutoTrader EchoPark Automotive 400 victory on a steamy-hot highly-dramatic afternoon of NASCAR Cup Series Playoff action at Texas Motor Speedway.

It marks a historic 300th victory for the championship Hendrick Motorsports organization – the most in NASCAR history for a NASCAR Cup Series team – and is the series-best, personal-high single-season sixth victory of the year for the 25-year-old Charlotte native Byron. He came from third place on the final restart to ultimately drive away from the field and take a 1.863-second victory ahead of Trackhouse Racing’s Ross Chastain to claim an automatic berth in the Playoffs’ Round of 8 which starts in three weeks.

Those final six laps out front were the only laps Byron led all day. He turned in a fabulous final re-start in the race to pull ahead of 23XI Racing’s Bubba Wallace, who was out front on that start after leading a race-high, career-best 111 laps in his No. 23 23XI Racing Toyota. Wallace finished third, ahead of Joe Gibbs Racing teammates Christopher Bell and Denny Hamlin. All five drivers among the 2023 Playoff contingent.

“I finally got a good re-start at the end, and number 300 for Hendrick Motorsports, but [teammate] Kyle [Larson] really deserved this one, I’ve got to say, those guys were really fast all day and I hate it for them in the end,’’ Byron said, noting his teammate Larson’s crash while leading with 20 laps remaining.

“But man, it was awesome getting this car to the front. My car loved clean air. We just fought through traffic all day. My Liberty University Chevrolet was just tight back in traffic but had good pace. … it was a grind-it-out day and our team was there at the end and I’m really proud of this one as hot as it was, it was tough. We’ll take it and go on to the next round.”

As for the historic 300th win for his team, Byron grinned, “I don’t’ know if I can even put it into words, I was such a Hendrick Motorsports fan growing up as a kid, watching Jimmie Johnson and became really fond of Jeff Gordon as I got to know him. Just thankful for all the men and women back at Hendrick Motorsports. … just appreciate all Rick Hendrick has done for me. This is awesome. We’re really going to enjoy this one.’’

Wallace, who turned in a career day in his first career Playoff stint, was obviously disappointed in the final outcome. He started from pole position and his triple-digit laps out front were a personal best.

“Just choked,’’ Wallace said. “My worst re-start (of the day). Hate it for my team, hate it for [sponsor] McDonald’s. We deserved to be in victory lane but nothing’s ever guaranteed, you have to go out and fight for it and not give it away and that’s what I did.

“We struggled a little in traffic but kept our heads in the game, made great strategy calls all day and had track position. So good points day.’’

Larson had been out front for 34 laps and was racing alongside Wallace when his No. 5 Hendrick Motorsports Chevrolet got loose with 17 laps remaining and flushed into the outside wall. He looked strong all day leading 99 laps himself as Wallace’s strongest competitor for most of the afternoon.

“We just went in there side-by-side and I lost it,’’ said the 2021 series champion Larson, who finished 31st. “Pretty bummed, but happy for William and Mr. H. (Hendrick) Three hundred Cup series wins is incredible and a great night overall for our organization.’’

Stewart-Haas Racing’s Kevin Harvick, Roush Fenway Keselowski driver Brad Keselowski. – also a Playoff driver, Trackhouse Racing’s Daniel Suárez, JTG Daugherty Racing’s Ricky Stenhouse Jr. and SHR’s Chase Briscoe rounded out the top 10.

There were 11 caution periods on the day and multiple issues for the 12 Playoff drivers competing in this three-round series of races to decide which eight will advance to the next round. Byron’s victory is an automatic ticket. Several other Playoff drivers had impactful days – for the good and bad – as well.

Among the other Playoff competitors, RFK’s Chris Buescher finished 14th and JGR’s Martin Truex Jr. – the regular season champion – finished 17th. Defending race winner Tyler Reddick – Wallace’s 23XI Racing teammate – was 25th.

Team Penske’s Ryan Blaney (28th), Hendrick’s Larson (31st) and Richard Childress Racing’s Kyle Busch (34th) all suffered DNFs – all involved in incidents.

It was indicative of the afternoon with 10 Playoff drivers experiencing some sort of setback – from crashes, to pit road penalties to pit road issues.

Bell had jack issues early. Hamlin had a pit road door-to-door collision with his JGR rookie teammate Ty Gibbs but was able to continue, while Gibbs’ Toyota suffered enough damage he had to retire early.

Busch’s No. 8 RCR Chevrolet slammed into the outside wall only a couple laps after the two-time series champion had radioed to his team that he thought he had a front tire going down. He stayed out on track and ultimately suffered a rear tire failure on Lap 74, that slammed his Chevrolet hard into the wall. Busch drove it backwards all the way around the track and onto pit road, but the RCR team was unable to repair it.

“I was going to come to pit road and I second-guessed it and said, ‘I don’t think so, something’s wrong, something’s not right but it’s not a flat,’’’ Busch said. “Then all on its own, it just turned to the bottom of the race track in Turn 1, just swapped ends on me.

“Hate it for everybody. For sure I thought our car was top five today.”

With the victory, Byron earned the automatic ticket to the next round. Hamlin now leads the points standings by 37 points on the ninth place elimination line. Buescher (plus-22), Bell (plus-20), Truex (plus-19), Chastain (plus-12), Keselowski (plus-8) and Larson (plus-2) round out the top eight.

Wallace is the first driver below the elimination line – two points behind Larson. Reddick is three points off the elimination line, followed by Blaney (-11) and Busch (-17) heading to the always unpredictable Talladega Superspeedway next week for the YallaWood 500 (2 p.m. ET, NBC, MRN, SiriusXM NASCAR Radio). Chase Elliott is the defending race winner.