Brad Keselowski has opened up on the last flight he took with Kyle Busch, just days before the NASCAR great's passing last week at the age of 41.

The pair shared a great rivalry over the course of their Hall of Fame careers, with their relationship thawing somewhat over the last year or two as they entered their 40s.

Keselowski revealed that his fellow Cup Series champion was clearly feeling under the weather on the flight to Dover for this month's All-Star Race – not a surprise, given that he talked about his ongoing sinus-type issues at that race weekend – and admitted he didn't think much of it at the time.

The RFK team owner added that the flight was 'pretty much' the last time he saw his fellow NASCAR legend, with the nature of a race weekend meaning that they didn't really cross paths for the rest of the weekend at Dover.

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Keselowski opens up on last time he saw Busch

“I was flying to Dover last week with Kyle," he told People magazine on Monday, adding: "It was probably more by chance than anything else.”

He continued: “Kyle is normally a fairly gregarious person, very outgoing – and he wasn’t. He sat down one row behind me and next to me and fell asleep right away and I could tell he wasn't feeling well," adding that he "didn't really think that much of it, to be honest.”

“And that was pretty much the last time I saw him. We were in a race and you get in a race and you don't really see each other. So I saw him on the racetrack.”

Keselowski: Tough not to get closure on Busch relationship

Keselowski also shared a touching thought he'd had before Busch's death, that the pair would fully reconcile after their at-time acrimonious racing relationship and share a laugh about their past rivalry.

“I guess I had visions before his death of... actually, I thought about this multiple times: What's it going to be like when we're both in the Hall of Fame and we're doing some kind of ceremony together, whatever that might be?

"Will the hatchet be buried? I think so. And will we actually be able to share a laugh about it? I guess in my mind, I hope so and now obviously not.”

He added: “The hard part is the closure was supposed to be when we were retired and when we were done racing together and I don't think that's just for me, by the way. I think that's for a lot of people. And to not get that is tough.”

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