Hampton, GA (Sports Network) - Ricky Stenhouse Jr. made a last-lap pass on Kevin Harvick and then held off Brad Keselowski at the finish to win Saturday night's NRA American Warrior 300 Nationwide Series race at Atlanta Motor Speedway.

Harvick put on a clinic on this 1.5-mile racetrack, leading 157 of 195 laps and holding as high as a 15-second advantage over the field. But a late-race caution for a multi-car crash set up a three-lap shootout to the finish.

After the final restart, Harvick pulled away from the field and appeared to be on his way to victory. But Harvick lost momentum on the last lap, as Stenhouse moved ahead of him on the backstretch. Keselowski, who fell two laps behind earlier in the race due to two pit road speeding penalties, followed Stenhouse to take second.

Stenhouse, the defending Nationwide champion, crossed the finish line 0.16 seconds ahead of Keselowski for his fourth win of the season and the sixth of his career.

"I knew I had to get everything I could on the restart," Stenhouse said. "I got a good restart and stuck down on (Harvick) as hard as I could to slow him down. Then he started getting loose off of (turn) two. And the 22 (Keselowski) gave me a push on the front straight that helped me get to the lead."

After the race concluded, Harvick, who finished third, and Keselowski had a heated discussion on pit road. Harvick blamed his fellow Sprint Cup Series competitor for causing a caution with 12 laps remaining when Keselowski threw his water bottle out of his car. NASCAR officials displayed the caution for debris in turn one, but officials said afterwards the debris was not the water bottle.

Harvick disagreed.

"The caution came out when the water bottle went out the window, so they (NASCAR) can say what they want," Harvick said. "They throw cautions when they want to, and tonight they threw it and got what they wanted."

Harvick has not won in Nationwide since Sept. 2010 at Richmond (30 races ago).

"The 6 (Stenhouse) had been good on the restarts, running on the top side," Harvick said. "He had the car with the freshest tires. Then he had the guy, who threw the water bottle out the window to get the caution, pushing him from behind. That's a tough way to lose it."

Keselowski dismissed Harvick's accusation, saying he didn't know what forced NASCAR to display the yellow flag.

"I don't know if the yellow came out because of the water bottle," Keselowski noted. "I didn't know there was a yellow for a water bottle to begin with, so I don't know what's going on. That was the first I heard of it when Kevin came by."

Elliott Sadler, the current points leader, finished fourth, followed by Justin Allgaier and rookie Austin Dillon. Kyle Busch, Cole Whitt, also a rookie this year, Sam Hornish Jr. and Michael Annett completed the top-10.

Danica Patrick finished two laps down in 13th.

With the win, Stenhouse trimmed Sadler's lead from 19 points to 12. Hornish is now 32 points out of the lead, while Dillon trails by 37 markers.