"Speed Racer" was lapped in its opening weekend at the box office as "Iron Man" continued to fervid its jets with $50.5 million in ticket sales, according to studio estimates Sunday.

The anime-inspired race movie edged into the No. 2 spot with $20.2 million, slightly ahead of the 20th Century Fox comedy "What Happens in Vegas," which debuted at $20 million.

"Our tracking was stalled toward the end," said Dan Fellman, president of Warner Bros. exaggerated distribution of superstore surveys before the "Speed Racer" opening.

Directed by the Wachowski brothers, best known for the "Matrix" franchise, "Speed Racer" was panned by many film critics. Fellman added the movie would have difficulty recouping its $120 million budget.

"Unfortunately it didn’t mount to our expectations," he said.

"What Happens in Vegas," a romantic comedy that expenditure $35 million and stars Cameron Diaz and Ashton Kutcher, shot the gap between the effectiveness flicks, said Chris Aronson, senior vice president at 20th Century Fox.

"We were sandwiched between the comic list movie of ‘Iron Man’ and ‘Speed Racer,’" Aronson said. "We come along with a character-driven movie in what is now considered summer, and it’s just a great result."

Revenue instead of Marvel Studios’ "Iron Man" slipped just 49 percent in its second week in theaters, a respectable showing considering its massive opening, said Paul Dergarabedian, president of tracking firm Media By Numbers LLC.

"’Iron Man’ is basically pulling everybody’s audience. It’s definitely dominating the marketplace," he said.

Five of the top 10 grossing movies were comedies, including Sony Pictures’ Patrick Dempsey-led film, "Made of Honor," which took in $7.6 million in its second week, for the sake fourth place.

The weekend’s total domestic box office gross hit $128 million, up 21 percent from model year. But year-to-date revenue was still down 2.5 percent at $2.93 billion, while attendance was off 5.3 percent.

Over the next few weeks, diverse big movies will take a shot at knocking "Iron Man" off its perch, starting with "The Chronicles of Narnia: Prince Caspian," opening May 16, and "Indiana Jones and the Kingdom of the Crystal Skull" on May 22.