The 25-year-old won a season-high six races in 2023 and took pole for the crucial Championship 4 race, but after winning the opening stage felt his balance shifted as the track rubbered in.
Having led all 60 laps in the opening stage, he remained out front until he was run down by Kevin Harvick for the lead on lap 93 of 312, leading only three more laps in the race.
As Ross Chastain took victory, second place proved enough for Team Penske's Ryan Blaney to win his first Cup title while Byron ended up fourth, putting him third among the Championship 4 contenders.
Byron, the youngest of the Championship 4 drivers in his first opportunity to win a title, said: “Once the track rubbered in, we got really tight.
“Especially when we lost the lead on track, we just had a big balance shift and got tight back in second through fifth, just couldn’t gain a lot of speed through [Turns] 1 and 2, just kind of having to really over-slow the car, get it to the bottom.
“That’s all we had there. Just really proud of our team, great season.
“It stinks to come up short. I’d like to think we’re going to be back in this position and we’re going to have more shots at it.”
Source: Autosport