Roger Federer and Elmo from Sesame Street seem to disagree on the letters of the alphabet in a Super Bowl ad for ON running shoes.

Watch as Elmo sits in an umpire's chair and debates the two letters found on Federer's On-branded sneakers: Is it 'Q' and 'C' or 'O' and 'N'?

Roger Federer is a marketing powerhouse on his own, and it's best put in Nike's former tennis director Mike Nakajima's words ...

Roger Federer certainly had no problem occupying his time after finishing his professional career. The former world No.1 said ...

The adored children's character jokingly criticized the tennis great over his spelling abilities. By cleverly tackling the widespread uncertainty about the brand's logo, the advertisement turns it ...