Keselowski and his RFK Racing Ford team-mate Chris Buescher led a combined 74 of the 212 laps, with Keselowski leading the most with 42, and he won the first stage.
But they lost their stranglehold at the front of the field with four laps remaining, when Richard Childress Racing Chevrolet pairing Kyle Busch and Austin Dillon drafted past their Mustangs, with more Chevys pushing them from behind.
As the race went into overtime following a late caution, Buescher, Keselowski and William Byron combined to ram Dillon into a spin that triggered a multi-car wreck and sent the race into a second green-white-checker attempt.
Buescher and Keselowski were also forced to pit for fuel, and Keselowski became caught up in the last-lap wreck just after the white flag, and was classified 22nd, while Buescher avoided the chaos to finish fourth.
“That’s the thing about [restrictor] plate racing, you make all these plans,” said Keselowski on FOX’s RaceHub show on Tuesday. “And you know what they say about plans: If you make plans, that’s how you make God laugh. Everything just fell apart really quickly.
“The 8 car [Busch] did a great job working with the 3 [Dillon] to get outside of us and I was still thinking we were going to be OK, then we had that spin with just a few laps to go.
“Overall, a really strong showing for us at RFK, we had two great cars, Chris and I led a bunch of laps, and I thought we did a really good job of controlling the race. I just wish we coulda controlled the finish.
“But it was nice to come out of there in the top 10 in points [thanks to his stage victory], for sure.”
After the race, Dillon had put the blame squarely on Keselowski for causing the penultimate wreck of the race.
“The 6 car [Keselowski] just drove through the 24 [Byron], and that is just what he does,” said Dillon. “His car is just good enough to where he can just drive through who he needs to and push them out of the way, or wreck them. That is the desperation that they are in right now.”
Byron said of the crash: “I got into the 3 and we just got off center somehow and I wrecked him. Once he got off center, I tried to back up but I had the 6 in the back of me trying to push as well. That was unfortunate.”