Los Angeles ? A martial arts dream team – Jackie Chan and Jet Li – won the weekend as their movie matchup “The Forbidden Kingdom” debuted at No. 1 with $20.9 million in ticket sales, according to studio estimates Sunday.

The tale of a modern American teen hurtled back in time to a kung fu adventure in ancient China, “The Forbidden Kingdom” features Asian superstars Chan and Li in multiple roles and their first big-screen duel.

“I couldn’t believe it had never been done before,” said Harvey Weinstein, whose Weinstein Co. released “The Forbidden Kingdom” along with partner Lionsgate.

Universal’s romantic comedy “Forgetting Sarah Marshall,” starring Jason Segel as a nice guy who’s dumped by his glamorous girlfriend (Kristen Bell), opened in second place with $17.3 million. It’s the latest from producer Judd Apatow (“Knocked Up”).

Al Pacino’s serial killer thriller “88 Minutes,” from Sony’s TriStar Pictures, was a dud, premiering at No. 4 with $6.8 million. The movie stars Pacino as a crime profiler who receives a call telling him he has 88 minutes to live.

“Expelled: No Intelligence Allowed,” a rare documentary opening in wide release, debuted at No. 9 with $3.1 million. Released by Rocky Mountain Pictures, the film features Ben Stein as he challenges Darwinian theories that prevail in academic circles and suggests that life could have emerged through intelligent design.

In narrower release, the Weinstein Co. documentary “Where in the World Is Osama bin Laden?” bombed with just $143,299 in 102 theaters, averaging a paltry $1,405 a cinema. “Forbidden Kingdom” averaged $6,623 in 3,151 theaters.

Estimated ticket sales for Friday through Sunday at U.S. and Canadian theaters:

1. “The Forbidden Kingdom,” $20.9 million.

2. “Forgetting Sarah Marshall,” $17.3 million.

3. “Prom Night,” $9.1 million.

4. “88 Minutes,” $6.8 million.

5. “Nim’s Island,” $5.7 million.

6. “21,” $5.5 million.

7. “Street Kings,” $4 million.

8. “Dr. Seuss’ Horton Hears a Who!”, $3.5 million.

9. “Expelled: No Intelligence Allowed,” $3.1 million.

10. “Leatherheads,” $3 million.