John Isner makes Roger Federer claim after Novak Djokovic breaks Wimbledon record

Novak Djokovic is bidding to win his eighth Wimbledon title (Picture: Getty)John Isner believes Novak Djokovic has surpassed Roger Federer as the greatest grass-court player in history as he chases yet another Wimbledon title.Djokovic, 39, is bidding to win a record-breaking 25th Grand Slam title and join his great rival Federer with eight Wimbledon wins.The Serbian legend has only dropped three sets on his route to the quarter-finals, where he will face Canada’s world number four Felix A