Chad le Clos and Michael Phelps resume battle in the pool, Katie Ledecky goes in search of more gold and Simone Biles aims to win a maiden Olympic title in an action-packed day at Rio 2016.
As many as 15 gold medals are up for grabs on day four of the Games, while Andy Murray continues his bid to retain the singles title in tennis.
LEGEND PHELPS SET FOR ANOTHER CLOS ENCOUNTER
There was high drama in the men's 200 metre butterfly four years ago at London 2012 when South Africa's Le Clos put in the performance of his life to pip the most decorated Olympian of all time to gold.
Le Clos is back to defend his title at the Maria Lenk Aquatics Centre, but he only placed third in his semi-final behind Phelps on Monday.
Phelps, who has 23 Olympic medals to his name, has already won gold in the 4x100m freestyle in Rio and is aiming to beat his rival to clinch a third Olympic gold in the event.
However, both men must be wary of the threat of Hungary's Laszlo Cseh, who is the current world champion, while Cseh's compatriot Tamas Kenderesi was quickest in the semis.
SJO-DOWN FOR LEDECKY IN WOMEN'S 200M FREESTYLE
Ledecky has already displayed her immense talents in the pool by swimming a world record time of three minutes and 56.46 seconds to win gold in the 400m freestyle.
The 200m is not recognised as her strongest event and she was beaten by Sweden's Sarah Sjostrom in their semi-final on Monday.
Sjostrom beat her own world record in the 100m butterfly to take gold on Sunday, and she and Ledecky are primed for a thrilling battle in the 200m freestyle.
BILES HEADLINES WOMEN'S TEAM GYMNASTICS FINAL
Simone Biles is one of the poster girls of the Rio Olympics and it would take a huge upset to deny the extremely gifted 19-year-old a first Olympic gold medal in the women's team artistic gymnastics final.
Having been too young to compete at London 2012, Biles is desperate to add to the plethora or World Championship golds she has accrued.
And with Team USA having dominated qualifying, Biles will be hot favourite to stand atop the podium with the rest of the team.
MURRAY OUT TO CAPITALISE ON DJOKOVIC SHOCK
When Andy Murray won gold at London 2012 it set in motion the wheels for his grand-slam triumphs at the US Open and Wimbledon in the following 12 months.
Fresh off winning Wimbledon for the second time last month, Murray is in great form and has the benefit of knowing he cannot face old foe Novak Djokovic following his shock first-round defeat to Juan Martin del Potro.
Murray faces off against Juan Monaco in round two on Tuesday, with Rafael Nadal is also in action against Andreas Seppi.