Ash Barty suffers more heartbreak in brutal Olympics moment

Ash Barty has been knocked out of the doubles event at the Olympics in heartbreaking fashion after a close match-deciding tiebreak at the quarter-finals stage.

Barty and Storm Sanders couldn't hold off a spirited Czech pairing of Barbora Krejcikova and Katerina Siniakov after falling in a match tiebreak in soaring heat.

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The World No.1 Aussie suffered heartache in her first round singles loss on Monday, which took the Olympics by surprise.

But, Barty has looked looked in good form with doubles partner Sanders as they started on fire and took the first set against the highly seeded doubles pair.

Krejcikova and Siniakov fought back in the second to level the match heading into a deciding tiebreak.

The Czech pair proved why they have won three Grand Slam titles together after holding out to win 3-6, 6-4 (10-7) to advance to the semi-final.

Storm and Barty are childhood friends, but have only paired together in doubles on two occasions as professionals.

However, against Krejcikova (World No.2) and Siniakov (World No.3) they were no match in the quarter-finals.

Barty caused a stir when it was announced she had entered into the mixed doubles event in Tokyo.

Ash Barty and Novak Djokovic cause a stir

The tennis world erupted with delight on Tuesday after it was announced that World No.1s Barty and Djokovic will play in the mixed doubles event at the Tokyo Olympics.

Barty and Djokovic were both listed in the 16-team draw on Tuesday, with the Aussie teaming up with John Peers and Djokovic with Nina Stojanovic.

It means Djokovic now has the chance to win gold in singles and mixed doubles, while Barty's chances of a medal also increased with the Aussie star still alive in the women's doubles.

Djokovic, who is chasing a rare 'Golden Slam' (all four majors and Olympic gold in the same year) is through to the third round in singles.

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