Sam Stosur was left lamenting a costly error which sent Australia's quest for a London Olympics tennis medal down the gurgler.

Australia's last hope at Wimbledon was extinguished on Saturday when mixed doubles pairing Stosur and Lleyton Hewitt went down to Great Britain's Andy Murray and Laura Robson 6-3 3-6 10-8.

Murray and Robson then beat Germany's Sabine Lisicki and Christopher Kas 6-1 6-7 (7-9) 10-7 to move through to the gold medal match on Sunday - when Murray will also play for gold in the men's singles against world No.1 Roger Federer.

Stosur, who bombed out on the opening day of competition in both the singles and doubles to continue her poor record on grass, rued a badly botched forehand off Robson's serve in the super tie-breaker to set up match point for the host nation - which they claimed when Stosur netted a volley.

"Those super tiebreaks can go any way and we definitely had the lead and the momentum and I got a bit tight on one of those returns to go down match point," Stosur said.

"Things can turn very quickly.

Stosur, ranked No.5 in singles, admitted Robson - ranked 98 - got the better of the two women players in the match.

"She definitely was playing very well," Stosur said.

"She was picking my serve and always putting me under pressure and when you've got to serve to Andy, that's not a fun prospect, either.

"We tried to mix it up and Lleyton was great at trying to keep them off guard and, in the second set, it got a bit better and we managed to pull it out to a super tiebreak."

Hewitt, who also lost in the third round of the men's singles to Novak Djokovic, wouldn't be drawn on whether this would be his last Olympics.

"I don't know. We'll have to wait and see," he said.

Murray said he was focused on the mixed doubles despite his desperation to win singles gold as well.

"A medal is a medal, it doesn't matter what it's in, whether it's in singles, doubles, mixed," Murray said.

"It all counts for the same so I want to try and win a medal in the mixed if we can and give it everything tomorrow for sure.

"I'm sure by the end I will be a bit tired, things will be a bit sore, but it will be worth it."

NZ Newswire

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