NASCAR legend Denny Hamlin has opened up on the evolution of his relationship with Kyle Busch, both over their 15-year period as team-mates and beyond.

The pair of future Hall of Famers were paired up at Joe Gibbs Racing for 15 seasons – longer than any other team-mates in history – after Busch came over from Hendrick Motorsports for the 2008 season.

56 of Busch's 63 Cup Series wins came as Hamlin's team-mate and, speaking to the media after Busch's tragic passing at the age of just 41, the driver of the team's No. 11 Toyota explained how his former colleague made him a better driver.

He specifically mentioned the difference in their racing backgrounds, with Busch – whose father was a mechanic – being much more hands-on with his cars compared to his older team-mate.

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Hamlin opens up on Busch partnership

"I mean, it was eye opening for one," he said of Busch's arrival at the team in '08. "When I signed my deal with Joe Gibbs Racing as development driver, it was kind of, I think it was the first year he going to run full-time with Hendrick in the O’Reilly Series.

"I just remember that, it was kind of him and Martin (Truex) and just those two guys going back and forth and just he was really, really good, but I didn't really know until he got in the same equipment that I got in and I could see how fast he was and just generally how good he was.

"At that point, it was like this is going to be super challenging to be the fastest and the best at your organization. You are going to have a really tough time, as long as this guy's your teammate. So just at that point when he came over and obviously set the world on fire, it certainly was eye-opening to me."

He continued: "To see kind of how in-depth he was with the race cars quite a bit different style than myself personally. But that was just kind of how he grew up is being super hands-on with the cars and he was very in tune with wanting to be involved with setups and things like that strategy.

"I was just a feedback kind of person. That was it you were just going to get the driving side of that from me. So it certainly challenged me to evolve and when I came into NASCAR itself, it was like, I come from short tracks. I didn't come from a mile and a halves and stuff like this. It just was such an important part of my development process to have a teammate like him that was good at stuff like this, that I could learn from.

"So there's no question, there was many, many instances where me and Kyle got to switch cars at a test, and at that point when I sat in the cars, I was like, okay, so this is what a winning car feels like. This is just not the direction that I would think, and then vice versa, we go to short tracks, he’d get in and be like, man, it's a lot different than what I would shoot for, and that combo is what made us more rounded than we ever were as race car drivers, just having that opportunity. I'm just super grateful for the opportunity to work with them as long as I did.”

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