Screenrant.com was able to interview Vin Diesel and here is what he had to say!
"I'm excited about Baby Groot; he's just too fun," he said of his character in Guardians 2. After Groot sacrificed himself in the closing moments of Guardians of the Galaxy, he was reborn as a small sprout, which he'll remain for at least the majority of Vol. 2. But after this year's space epic, it's time for the MCU to clash good and proper, and Diesel can't wait.
"In Infinity War, I have to talk to the Russo brothers [directors of the film] and find out how this is all gonna go down. I know somewhere in the Marvel Universe, there is a moment when you will see Groot and Hulk have a few words," he teased. That's a pretty definitive statement that we'll see the bruisers of their respective teams get into some fisticuffs. "I think there's gonna be a moment that we're allwaiting for, and whether you know it our not, you are waiting to see Groot and the Hulk get down."