NASCAR star Denny Hamlin has promised 'no mercy' for Noah Gragson for the rest of the season.

Hamlin found out that the Front Row Motorsports driver made the active decision to keep the No. 11 car a lap down rather than allowing him the chance at the free pass thanks to radio chatter, and addressed the moment on his Actions Detrimental podcast this week.

The Joe Gibbs Racing driver had gone a lap down early thanks to a penalty for speeding on pit road, and ended up spending the majority of the race just waiting for a chance to get back on the lead lap.

Compounding his frustration was the fact that he had helped Gragson's FRM team-mate Todd Gilliland stay on the lead lap just a week previous at Kansas...but didn't get anything like the same treatment from the team at Talladega.

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Speaking on the incident on Monday, he said: “Really? This is the same Front Row team that I let back on the lead lap last week?…Really? Okay. Well, when it comes back around, when I go to lap Noah at one of these races, I’ll make sure I have no mercy then.”

Hamlin intimated that he believed the order to keep him a lap back came from above rather than Gragson himself – only for Gragson to claim the exact opposite on the Door Bumper Clear podcast on the same day.

“Guess what? I’d do it again," he said. "My team didn’t know the rule and I’m like, yeah, if we pit, then we can trap those guys a lap down still and then it gives us a one-lap buffer if we wreck at the end of the race.”

The admission shows an impressive grasp of the rules on the fly, from a driver who got his qualifying time kicked out at Daytona this year for – by his own admission – completely forgetting about a rule that everyone had been talking about in the lead-up to the session.

After driving happily down the straight with his hand up to change the air flow, the driver of the No. 4 car admitted to FOX at the time: "I completely forgot about that rule, so that one is on me.

"Luckily we have the Duels and I feel like the Daytona 500 is such a long race, you can kind of start wherever. It is what it is, but hey, I feel like an idiot for that. Oh well, we got a race tomorrow to do ... I'm dumb for that."

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