Kevin Harvick appeared in command on his way to win at Phoenix when a late-race caution for a spin by Harrison Burton sent all the lead-lap cars into the pits.
The top six each took on only two new tyres, but Kyle Larson was first off pitroad, only for another crash shortly after the restart with three laps to go sending the race into a two-lap overtime.
On the ensuing restart, Byron went to the outside of Larson and with a shove from Tyler Reddick, powered into the lead with one lap to go.
Byron then held off Ryan Blaney by 0.330 seconds to secure his second straight NASCAR Cup win and sixth of his career.
“We owe the last couple weeks to him,” Byron said of his crew chief, Rudy Fugle. “He’s done a really good job strategy-wise and execution-wise and we’ve done a good job to put ourselves in those positions on the front row with a shot at the end.
“Thanks to everybody back at Hendrick Motorsports, putting together great cars, doing a great job. This is a big credit to them.”
Race winner William Byron, Hendrick Motorsports, Chevrolet Camaro
Photo by: John Harrelson / NKP / Motorsport Images
After his difficult start to the 2023 NASCAR Cup campaign, with 34th in the Daytona 500 and 25th in Fontana, Byron’s consecutive wins pushes him to fourth in the overall drivers’ standings, with Alex Bowman narrowly holding on to the points lead with ninth place at Phoenix.
Reddick ended up third, to see Larson, who led the most laps in the race with 201, miss out on the podium in fourth.
Harvick cut an equally downbeat figure having been the leader before the initial late-race caution period, as he dropped down to fifth place at the chequered flag.
Christopher Bell took sixth place ahead of Chase Briscoe, Kyle Busch and Bowman, as Josh Berry, who was in his second start filling in for the injured Chase Elliott, completed the top 10.
There was further drama on the final lap, when Denny Hamlin appeared to go up the track and into Ross Chastain as both hit the wall. Hamlin was credited with a 23rd place finish and Chastain 24th.
NASCAR Cup – Phoenix race results – 317 laps