When it comes to the characters of Henry ‘Razor’ Sharp and Billy ‘The Kid’ McDonnen in the boxing comedy Grudge Match, played by Sylvester Stallone and Robert De Niro, the old adage about it not being the size of the dog in the fight but the fight in the dog rings true.

After fighting twice in their prime and tying at 1-1, there’s plenty of unfinished business. The tie-breaking fight never happened, and 30 years have not softened the bristling tension between the now bona fide senior citizens. But a chance encounter between the two to do some green screen work for a video game erupts into a brawl that reignites their rivalry and stokes the public’s interest in a third fight.

The comedy kicks as both men shake off years of inactivity to try and get shape to right the wrongs of their past. Stallone, 67, and De Niro 70 have both featured in classic boxing movies (Stallone for his Rocky franchise and De Niro won an Oscar in 1981 for playing Jake LaMotta in Raging Bull), and both men look like they made a decent effort to get in fighting shape.

The movie, which hits the big screen on Christmas Day, is directed by Peter Segal and also stars Alan Alda, Kim Basinger, Kevin Hart and Jon Bernthal.