Wozniacki follows Djokovic to exit tennis
Caroline Wozniacki crashed out in the second round to the Czech Republic's Petra Kvitova yesterday.
Twice Wimbledon champion Kvitova overpowered Denmark's former World No 1 6-2 6-4 to progress to the third round.
Elsewhere, Novak Djokovic admitted his shock first-round defeat to Juan Martin Del Potro was "one of the toughest losses of his life" as his hopes of claiming Olympic gold in the men's singles went up in smoke.
Djokovic, who also lost to Del Potro in the bronze medal play-off at London 2012, had no answer to the power of the Argentinian, with the 2009 US Open champion sealing a 7-6 (7/4) 7-6 (7/2) victory in almost two and a half hours.
Phelps adds 19th gold
Michael PHELPS began the final chapter of his storied career with more glory as he helped the US men's team to victory in the 4x100m freestyle relay to collect his 19th Olympic gold medal.
With the US men having reached the podium in every 4x100 freestyle relay since the event was introduced in 1964, there was every chance Phelps was going to add to his haul.
Elsewhere, Katie Ledecky of the United States broke her own world record on the way to winning the women's 400m freestyle gold medal, the first stage of a rare treble she hopes to complete in Rio.
PADRAIG HARRINGTON will play alongside Italy's Matteo Manassero and New Zealand's Danny Lee when he tees off at 11.41am for the Olympic tournament on Thursday morning.
Seamus Power is drawn with India's Shiv Chawrasia and Chinese Teipei's Lin Wen-tang at 2.47pm.
'Course is fine' - UCI
The sport's governing body the UCI said the Olympic course was not to blame for a series of bone-crunching crashes during the weekend's road races around Rio's stunning coastline.
Dutchwoman Annemiek van Vleuten fractured three vertebrae and suffered concussion in a horrible crash while leading on the descent close to the finish, but tweeted yesterday that she was 'fine'.
The UCI said in a statement: "The course was carefully designed and was extensively tested at the test event and in training."