Nurmagomedov backs Rafael dos Anjos to beat Pettis at UFC 185 on March 14 in Dallas.
In a chat with MMAFighting.com, Nurmagomedov backs Dos Anjos all the way.
"I think Dos Anjos smashes Pettis in striking and I think he smashes him on the ground," Nurmagomedov said. "This is my opinion. I don't know why, but I think he'll smash him."
Second-ranked Nurmagomedov has been out of action with an injured knee since his last fight when he beat Dos Anjos at UFC on FOX 11 last April.
"Dos Anjos is no easy man," Nurmagomedov said. "A lot of people watch and think I beat him easy, but it was not easy. It was no easy fight.
"I beat him, but nobody beat him like me."
Pettis and Nurmagomedov have been using social media and interviews to comment at each other over a number of things.
The champion recently told MMAjunkie that Nurmagomedov's trash talk is "annoying" but that he is only an amateur.
"He only gets by on his wrestling," Pettis said. "He thinks his striking is going to be good enough to survive against me, take me down and grind me out for 25-minutes? He's never done that. He's never fought a main event for 25 minutes.
"Anybody can wrestle for 15-minutes, but it's different when you're fighting for the title. At the same time, his striking is amateur compared to where my wrestling is. My wrestling is on a way higher level than his striking if you want to compare the two," he added.