The two veteran actors are starring in the new comedy "Grudge Match" about two retired boxers, long past their prime, who've held a bitter rivalry against each other for over three decades.
De Niro, 70, and Stallone, 67, last starred together in 1997's "Cop Land," and both actors have previously garnered acclaim for their portrayal of boxers. Stallone was nominated for two Oscars for the original "Rocky," and De Niro won a best actor Academy Award for his portrayal of Jake LaMotta in Martin Scorsese's 1980 classic, "Raging Bull."
In a recent interview with CBS News, Stallone said that he and De Niro made up the perfect odd couple. Stallone was the jokester on-set, while De Niro kept things serious.
"That contrasting is really important," Stallone revealed. "You don't have two characters trying to outdo each other. If you've ever done a scene where a guy's ad-libbing, he wants to out-ad-lib you, it doesn't stop. This was very very beautifully balanced."
Watch the video above to see De Niro and Stallone discuss the film along with their co-stars Kim Basinger, Alan Arkin and Kevin Hart. Don't miss a hilarious bit towards the end of the video where Hart and Arkin make light of the film's take on aging.
"Grudge Match" comes to theaters on Dec. 25.