Argentina's Juan Martin del Potro stunned Roger Federer in four sets to reach the US Open semi-finals. The 24th seed won 7-5 3-6 7-6 (10-8) 6-4 to reach the last four, thrilling his large contingent of supporters in New York.
Venus Williams’s renaissance year continued on Tuesday when she downed Petra Kvitova 6-3, 3-6, 7-6(2) in an electrifying atmosphere to set up an all-American US Open semifinal against Sloane Stephens.
