Martin Truex Jr. assumed the lead when Joe Gibbs Racing teammate Kyle Busch was penalized for speeding with about 50 laps to go and won the f Cup Series race at Richmond Raceway on Saturday night.

(Sean Gardner/Getty Images)

The victory was the third for Truex in the last five races at Richmond. He got the lead when Busch was caught speeding entering pit road during green flag pit stops, causing him to relinquish a big lead and fall back to 10th.

Truex led a 1-2-3 finish for JGR — the sixth in its history — with Denny Hamlin finishing second and Christopher Bell third.

Truex won despite being black-flagged on the first lap for beating Hamlin, the pole-sitter, to the start-finish line for the start of the race.

"That was frustrating, I'm not going to lie, but I knew we had a good enough car to overcome it," Truex said about the penalty.

His car bore a red, white and blue paint scheme as part of the day-long tribute to honor the victims and heroes of the Sept. 11 attacks 20 years ago.

"It’s an important day in our history and I think all of us here -- yeah, we’re proud to win and this car’s amazing and there’s so many people to thank, but what a day to win on," Truex said in victory lane. "It reminds you of the honor it is and the privilege it is to get to come out here and do this."

Hamlin trimmed an 8-second deficit to 1.4 seconds, but ran out of time.

"We needed just a couple more laps. That’s all." Hamlin said.

Bell has won three times on the 0.75-mile oval in the NASCAR Xfinity Series.

"We knew going into Richmond that this is one of our better racetracks, so we needed to capitalize on that and get all the points we could," he said.

Truex's penalty sent him to the back of the field, but as he has done repeatedly since ending an 80-race winless drought on tracks shorter than a mile at the start of his career, he masterfully worked his way back into contention.

The victory was his fourth of the season and the 31st of his career.

Defending series champion Chase Elliott was fourth, followed by Joey Logano and points-leader Kyle Larson, who started the race at the back of the field after twice failing pre-race inspection. Larson finished sixth and did clinch his spot in the second round of the playoffs, which start after next weekend.

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Hamlin, as he did in the spring here, won both stages and led the most laps — 207 in the spring, 197 in this race — but failed to follow his victory last weekend with another on the track about 20 miles from where he grew up.

PRE-RACE TRIBUTE

Fans were given small American flags as they entered the track and were encouraged to stand and wave them as a fire truck and two police SUVs, all with lights flashing, led the pace vehicles on the pre-race parade laps.

As the tribute unfolded, a chant of "USA! USA!" erupted in the stands.

POINTS RACE

Hamlin cut 10 points off Larson's lead — from 34 to 24 — with Truex another 14 points back. They are the only three to have clinched Round of 12 berths.

"So very good to be able to do this and go to Bristol without any worries next week," Truex said.

PLAYOFF PROBLEMS

William Byron and Michael McDowell's playoff experiences are going poorly.

Byron finished 34th last week at Darlington and 19th at Richmond. McDowell finish 37th — last — last week and had three speeding penalties and finished 29th at Richmond. The third penalty came while he was serving the second.

Byron is 15th in points, 116 behind, and McDowell is 136 behind.

UP NEXT

The series wraps up the opening round of the playoffs, and narrows the championship field from 16 to 12, on another short track with the annual Saturday night race around the high banks of Bristol Motor Speedway.