Sly's Not Gonna Fly in 'Grudge Match' Montage

Sylvester Stallone and Robert De Niro play on their respective Rocky and Raging Bull roles in the hilarious boxing comedy Grudge Match, and we have a first look at new scenes from the movie that feature Sly's training with "legendary trainer Lightning Conlon," played by Alan Arkin. Gonna Fly Now? Not exactly... Watch the video!

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In theaters everywhere Christmas Day, Grudge Match casts Stallone and De Niro as old boxing rivals who come out of retirement for one final match to settle the score once and for all. But they may not even make it to the ring, as their first encounter in decades ignites their long-festering feud -- and a viral video of an unintentionally hilarious melee transforms their local grudge match into a must-see HBO event.

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Directed by Peter Segel (Get Smart, Anger Management), Grudge Match also stars Kevin Hart, Kim Basinger and Jon Bernthal.