Athens silver medallists Nathan Robertson and Gail Emms today won an epic badminton battle against the No2 seeds, Ling Gao and Bo Zheng.

The British mixed doubles' pair triumphed 21-16, 16-21, 21-19 to silence a vociferous home crowd at Beijing's BJUT Gymnasium and give them an excellent medal chance in what is almost certainly their last tournament together.

The victory sets up a quarter-final with Hyojung Lee and Yongdae Lee, of South Korea, and also means they can't meet No1 seeds Nova Widianto and Liliyana, of Indonesia, until the final.

Robertson said: "We love playing, we love winning, we hate losing. When the Olympics is going on, it's something special. If we play well, we could be the best pair in the world."

Gao was part of the Chinese duo that beat Robertson and Emms in the 2004 final, so today's result was sweet revenge in a highly-charged encounter.

Emms said: "Throughout the whole game I enjoyed it, you have to enjoy it when you are playing like that."

The 2006 world champions have slipped down the rankings in the past two years due to Robertson's ankle injury which explains why they faced such highlyrated opponents in only the first round.

However, there were no signs of any rustiness as they dominated the early stages of the opening game with an unstoppable combination of intelligent defence from Robertson and vicious smashing from Emms. The 31-year-old from Hitchin, who has declared this her last Olympics, was bursting with energy and pumping her fist with excitement at every opportunity.

Robertson responded to the motivation and came through with a series of crucial winners at the business end of the match.

After racing into a 15-9 first-game lead, the duo wavered a little before key smashes from Robertson and then Emms set up five game points at 20-15. An error from Gao clinched the game to 16 when she served into the sidelines.

The British pair started where they left off in the second game and signs of cracks in the Chinese pair's composure started to emerge, with Gao berating her partner as they slumped to 7-3 down.

The impromptu pep talk, however, seemed to work wonders, with Zheng suddenly raising the aggression levels as the hosts overturned the deficit. A forehand error into the net from Emms eventually handed their opponents the game 21-16.

The Chinese seized the initiative from the very start of the decider and Zheng's strength helped them establish a formidable 16-10 advantage. But Emms and Robertson rallied for one final effort and courageously fought back to 17-17 as Chinese nerves started to show.

An immense overhead from Robertson gave them the lead for the first time in the game at 18-17 and a leaping smash then took the score to 19-17.

After the Chinese hit back to level at 19-19, tension in the arena was at its height when Robertson forced an error to set up match point. The 31-year-old from Nottingham then sealed a magnificent fightback with a cross-court smash after pressurising Gao on her backhand.

As the winner landed in court, the pair lifted their arms in relief as much as jubilation. Robertson said: "In the third game I was just so determined. This could be our last tournament and I just didn't want it to end.

"They were feeling the pressure. To come back against the Chinese like that is unusual. It's so difficult against them to get a run of points like that."

He claimed the partisan home crowd, which repeatedly cheered their mistakes, had no effect on the pair's performance, adding: "When you're playing you don't notice they are against you. You're just so into it although I guess it helps your energy."

Energy was hardly in short supply for Emms either, as her fist-pumping antics and shouting kept the pair focused.

She said: "You have to be pumped up on court and, if I can be in their face and show I am not scared, it means they know that they can hit me with anything they can and I can hit it back."

On the incredible third game turnaround from what seemed a lost cause, Emms added: "We could tell they were shaking and Nathan hit some great smashes. The momentum can change at any time and, even when we were down, I was enjoying every moment."

Their quarter-final clash is scheduled for 12.15pmon Thursday, with the final set for Sunday.