TMZ Sports talked to Khabib and Islam's longtime manager, Ali Abdelaziz, this week ... and while all MMA fans are well aware of Nurmagomedov's exploits inside the cage, we asked about his talents as a coach -- and how it's impacted Makhachev's preparation heading into UFC 302.

"[Islam] had one of the greatest coaches you can ever have in your corner, Khabib. He's been coaching in the whole camp," Ali said, adding, "He had some of the best training partners you can ask for mimicking Dustin. We're fighting a dangerous opponent. You know, Dustin Poirier is a dangerous opponent, but I feel right now Islam is a hard guy to beat, you know?"

"And, he's going there for the kill. Everybody talks about Dustin Poirier, he's killed or to be killed. Tomorrow, Islam is going to be turned into a killing machine."

Typically, coaches receive a percentage of a fighter's pay ... but not Khabib, not this time.

"Khabib came to camp. He's not making money. He's not getting a percentage. He's spending his own money for his own flight just to help his brother."

Of course, Khabib, 29-0 (BTW, one of those wins came against Poirier), retired after beating Justin Gaethje in 2020 ... shortly after the tragic death of his father, Abdulmanap.

Since, Nurmagomedov has dedicated himself to coaching ... although he has stepped aside at times (he wasn't in Islam's corner for the Volkanovski fight at UFC 294).

Check out the clip. There's much more with Ali on Islam, Khabib, and some of his other star fighters.