WATCH: Federer Coy on Trick Shot Video

The tennis champion was decidedly coy about the stunt where he apparently hit a metal bottle off someone's head with a serve during a commercial shoot. The video has been viewed on YouTube about 2.3 million times, and people have been busily trying to determine if it was real or was the latest sleight-of-mouse trick of video editing. If it's fake, then the person who put it together should be getting some credit.

"Oh, that thing?" Federer replied when asked about the video on Wednesday evening after winning a match at the Cincinnati Masters event. "Yeah. Well, there's a lot of debate at the moment, you know. You know how it is with magicians. They don't tell how their tricks work, you know."

Federer smiled. Don't try this at home.

"I don't do it that much, but, yeah, it was shot in one piece and it was - the guy took a chance," he said. "It worked out. I'm happy."

Federer, seeded third, advanced to the quarterfinals in a walkover on Thursday after his scheduled opponent, Philipp Kohlschreiber, dropped out with a shoulder injury.