Olympics Rio 2016: Phelps extends gold tally to 21To play this video you need to enable JavaScript in your browser.This video can not be playedOlympics Rio 2016: Phelps extends gold tally to 21CloseA round-up of the all the action from day four of the 2016 Olympic Games in Rio.SubsectionWorldPublished10 August 2016Shareclose panelShare pageCopy linkAbout sharingRead description