It was in the movie Forbidden Kingdom, released April 2008.
The story of the movie is based on the Chinese epic “Journey to the West”, one of the four classic novels of Chinese Literature. The novel tells the story of the Buddhist monk Tang Sanzhuang’s pilgrimage to India during the time of the Tang dynasty to get some Buddhist scriptures.
Jackie Chan played Lu Yan / Old Hop, the famous Taoist Saint in Chinese mythology, while Jet Li played the Monkey King / the Silent Monk.
I agree with some people who commented that this should’ve been done earlier in their careers, when they were faster and stronger.
Still, this scene between two martial arts legends is definitely still worth watching.
youtube link (embedding disabled)
I wouldn’t say it’s the best on-screen match-up I have ever seen, there’s at least another film released in 2008 that had a better fight scene, and that Bruce Lee v Chuck Norris scene in the 1970s remains the reference standard.