The video shows Federer knocking a metal can off a man's head with a serve while shooting an ad for Gillette. Then, he does it again, drawing applause from the crew. Federer's official website had a link to the video.
There were questions about whether it's really a trick shot or a video trick. Following his opening match at the Cincinnati Masters on Wednesday night, he was asked directly whether the video is real.
"Not saying that," is how he responded. Then he added that "a magician doesn't tell how his tricks work."