With a nudge from behind Truex got around then-leader Ryan Preece with 24 of the 150 laps remaining and managed to stay out front despite two late-race cautions and subsequent restarts.
Joey Logano won the inaugural event last year and ended up winning the series championship, leading to good omens for Truex, who had been considering retirement last year before he signed another one-year deal with JGR to remain in the #19 Toyota.
Truex ended up winning ahead of Dillon by 0.786 seconds in a race that featured 16 cautions, with caution laps not counting in the event. For a second consecutive year the Clash race was held on a quarter-mile asphalt oval built inside the iconic coliseum.
Busch, Truex’s former team-mate at Joe Gibbs Racing, finished third ahead of Alex Bowman in fourth and 2021 NASCAR Cup champion Kyle Larson ended up in fifth place.
In a frantic and at times bad tempered Clash race, the finale was truncated by caution periods, as Dillon knocked Bubba Wallace out of the wall and into the Turn 2 wall with six laps to go.
Wallace then hit back at Dillon in retaliation under caution, before the race restarted on lap 144 with Truex out in front to take the win.
“Just a really good race car. The guys did a really good job,” Truex said. “Last year was a pretty rough season for us with no wins.
“To come here and kick it off this way, I’m just really proud of these guys. Tonight we just about perseverance and not giving up and just battling through. We found ourselves in the right spot in the end.”
Further back, Tyler Reddick claimed sixth place ahead of Preece – who led most laps in the Clash – as Ross Chastain, Denny Hamlin and William Byron rounded out the top 10.
The 2023 NASCAR Cup season officially gets underway with the Daytona 500 on 19 February, with the traditional pre-event Duels contest taking place on 16 February at the same venue.