Denny Hamlin claimed his fourth NASCAR Sprint Cup win of the season after holding off Jeff Gordon in a late restart at Atlanta, where the Chase field was almost fully set.
The Joe Gibbs Racing driver led 106 laps, more than any of his rivals during the night. It was Hamlin's last pitstop that proved key, allowing him to lead the final restart.
In the green-white-chequered finish, Hamlin came under attack from Gordon's Hendrick Motorsports Chevrolet. The former champion tried to drive around the outside of the #11 Toyota into Turn 3 but could not find enough grip to keep his run for the lead alive into the final turn.
Hamlin's win clinched his spot in the Chase. He currently leads the series for wins with four, potentially making him the play-off leader in two weeks' time.
"We just had such a strong car for three quarters of the race," said Hamlin. "The line I was running, I knew there was a price to pay if I kept going down there and it took its toll on our car by wearing the splitter out. That really hurt us at the end. Other than that I feel like we had the best car.
"Circumstances just fell our way in the end and when you start to falter and you start to fade you've got to have another aspect of the team that picks you up and today it was the pit crew that won us this race."
Gordon's second place allows him to remain in contention for the final Chase wildcard spot. Hamlin's team-mate Kyle Busch currently holds it following a sixth-place finish on Sunday night.
Penske's Brad Keselowski finished third and mathematically secured a Chase spot, as did Martin Truex Jr who was leading the race and looking on course for his first win for Michael Waltrip Racing before the final caution came out. Although he would resume in second, a poor restart put him out of contention for victory.
Kevin Harvick led 101 laps, having one of his best races of the season but his car lost its edge when running in dirty air. However, he also clinched a Chase seeding along with Clint Bowyer and reigning champion Tony Stewart, the latter thanks to his three wins.
Stewart started from pole for the first time this season but then struggled all night, finishing down in 22nd place and one lap behind the winner.
Carl Edwards' Chase hopes took a hit when he had to pit with an engine issue, which ultimately caused him to retire.
Stewart-Haas' Ryan Newman was involved in an incident caused by contact between Jimmie Johnson and Sam Hornish Jr and would not see the chequered flag either, losing massive ground in the battle for the final wildcard spot.
Results - 327 laps: Pos Driver Team/Car Time/Gap 1. Denny Hamlin Gibbs Toyota 3h32m45.000s 2. Jeff Gordon Hendrick Chevrolet + 0.378s 3. Brad Keselowski Penske Dodge + 0.568s 4. Martin Truex Jr Waltrip Toyota + 1.414s 5. Kevin Harvick Childress Chevrolet + 1.713s 6. Kyle Busch Gibbs Toyota + 1.916s 7. Dale Earnhardt Jr Hendrick Chevrolet + 2.314s 8. Paul Menard Childress Chevrolet + 2.531s 9. Matt Kenseth Roush Fenway Ford + 2.733s 10. Mark Martin Waltrip Toyota + 2.807s 11. Sam Hornish Jr Penske Dodge + 3.149s 12. Jeff Burton Childress Chevrolet + 3.396s 13. Kurt Busch Phoenix Chevrolet + 3.578s 14. Regan Smith Furniture Row Chevrolet + 3.982s 15. Greg Biffle Roush Fenway Ford + 6.535s 16. Trevor Bayne Wood Brothers Ford + 6.800s 17. Marcos Ambrose Petty Ford + 7.519s 18. Joey Logano Gibbs Toyota + 7.763s 19. Bobby Labonte JTG Daugherty Toyota + 8.413s 20. Landon Cassill BK Toyota + 1 lap 21. Juan Pablo Montoya Earnhardt Ganassi Chevrolet + 1 lap 22. Tony Stewart Stewart-Haas Chevrolet + 1 lap 23. Kasey Kahne Hendrick Chevrolet + 2 laps 24. Jamie McMurray Earnhardt Ganassi Chevrolet + 2 laps 25. Dave Blaney Baldwin Chevrolet + 3 laps 26. Travis Kvapil BK Toyota + 3 laps 27. Clint Bowyer Waltrip Toyota + 3 laps 28. David Ragan Front Row Ford + 4 laps 29. Danica Patrick Stewart-Haas Chevrolet + 6 laps 30. TJ Bell FAS Lane Ford + 8 laps 31. David Gilliland Front Row Ford + 29 laps 32. Aric Almirola Petty Ford + 30 laps Retirements: Casey Mears Germain Ford 291 laps Jimmie Johnson Hendrick Chevrolet 269 laps Ryan Newman Stewart-Haas Chevrolet 268 laps Carl Edwards Roush Fenway Ford 264 laps Scott Speed Leavine Ford 196 laps Jason Leffler Robinson-Blakeney Toyota 77 laps David Stremme Inception Toyota 54 laps Scott Riggs R3 Chevrolet 43 laps JJ Yeley Baldwin Chevrolet 32 laps Reed Sorenson Humphrey Smith Chevrolet 24 laps Joe Nemechek NEMCO Toyota 22 laps