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 ...

NPR's Ayesha Rascoe talks with director Dawn Porter. Her new documentary, "Luther: Never Too Much," tracks the life and music of the singing great Luther Vandross.