It initially appeared that David Reutimann would run away with the race (though he was pushing it on fuel mileage), but a caution flag fell with just 10 laps remaining after Brad Teague spun off of Turn 2. That bunched the field back up behind Reutimann for a restart on Lap 217 of 225.
On that restart, Reutimann was ambushed by Bowyer and Kyle Busch. Bowyer took the lead after contact with Reutimann but only temporarily, as Keselowski dropped his No. 88 Chevrolet to the inside of Bowyer's No. 2, taking the position.
"That's what we needed to catch back up to the 99 [Reutimann]," Keselowski said. "For some reason, David didn't go. I got behind him, took the air off of him and the next thing I knew I got by David and next was taking on Clint," Keselowski said.
"I feel like I paid some dues," he added after hoisting his first Nationwide trophy, which came in the form of a custon Gibson Guitar painted by Sam Bass.
"To catch that break like I did with Dale [Earnhardt] Jr. and this Navy Chevrolet, it vindicates it. I've got a team that just keeps getting better every week, and I keep getting better every week. I felt like this was just a matter of time."
As Keselowski drove toward the checkered flag, things got dicey behind him. Reutimann continued to get pushed around, as he dropped back to third as David Stremme slid into the second position.
Bowyer also had contact with Stremme, dropping him to fourth at the finish.
David Ragan closed out the top five finishers.
Reutimann, Bowyer, Ragan, Busch, Carl Edwards, Greg Biffle and Jason Leffler all flew to Nashville to compete in Saturday's race after taking part in Sprint Cup Series final practice at Pocono Raceway in Long Pond, Pa., earlier in the day.
Pole-sitter Logano led 64 laps in what marked his second series event. The early favorite to win, the 18-year-old was the victim of a four-wide race through Turn 4 on Lap 89. His No. 20 Toyota got clipped by Biffle's Ford, sending him sideways into Busch's machine before shooting up track and into the outside wall. He ended the event 31st.