British pair Andy and Jamie Murray were knocked out of the men's doubles in three sets by Jurgen Melzer and Alexander Peya in the Olympic tennis competition at Wimbledon.
The wildcard pair took the first set 7-5 after snatching an early break, but the match hinged on the second set tiebreak, which saw the Austrian pair draw level.
And with the British hopefuls having to serve out in the 12th game, Melzer and Peya pounced to reach round two at the expense of the home favorites.
While Jamie could have a mixed doubles campaign to look forward to following the disapointing exit, brother Andy begins his attempt to claim singles gold against Stanislas Wawrinka on Sunday.
Elsewhere, Anne Keothavong surrendered a first-set lead against Caroline Wozniacki, as the Dane eventually prevailed to reach the second round in three sets.
Keothavong, one of four British females wildcards in the singles draw, dominated the former world No.1 in the opening set, taking it 6-4, but the tide quickly turned in the second, as Wozniacki drew level.
And she refused to allow her dominance to drop, dispatching Keothavong in the third set.
Elena Baltacha overcame a shin problem to defeat Hungary's Agnes Szavay in straight sets to deliver some positive news from SW19 for Team GB.
"It's a very good start, I'm very delighted with that," she said. "I think for a first-round match I'm very happy with how I played. I'm chuffed to be in the second round now.
"I was quite nervous before the match. I think once I put my GB gear on, it relaxed me more because I've been looking forward to this for such a long time. I thought, 'I've got an amazing opportunity'.
"That kind of relaxed me a bit more. Once I started going on court, seeing all the home support, them getting right behind me, that got me more confident and more relaxed. So it was lovely."
Meanwhile, Wimbledon champions Roger Federer and Serena Williams won on the opening day of the Olympic competition, with the Swiss beating Alejandro Falla, while Serena defeated Jelena Jankovic.