Robertson and Emms won a thrilling semi-final against Thai pair Sudket Prapakamol and Saralee Thoungthongkam 21-18 17-21 25-23, while Clark and Kellogg outclassed Malaysian duo Koo Kien Keat and Wong Pei Tty 21-14 21-12. It will be England's first World Championship gold medal since 1983.

 

"I think it is the most important thing that has ever happened to English badminton, we are now guaranteed an English world champion," said Robertson.

 

"Anthony and Donna are our training partners, I've been close friends with Anthony for over 12 years and it is fantastic. This means that England will win the second most medals at this world championship."

 

Robertson and Clark share rooms as do women's doubles partners Emms and Kellogg and the two pairs also train together.

 

"I'll make sure I elbow Donna in the ribs tonight," joked Emms, while Robertson addded: "I'll make sure me and Anthony follow exactly the same routine again tonight. We'll go to the same restaurant, sit in the same seats and watch the same movie in the room.

 

"I wouldn't want to be playing anyone else in the final. It is perfect."

Robertson and Emms, the Olympic silver medallists, trailed 11-15 in the decisive game, but fought back to go 20-18 up. However, nerves seemed to get the better of the pair who needed six match points before wrapping up the win.

 

 

"One English pair had already got in the final and I was thinking it would be bloody disappointing if we didn't get there too," said Robertson. "But although we didn't play that well we showed the determination to get through."

 

It is the first time that there has been an all-English mixed doubles final and will be the country's first gold in the event since Nora Perry won the world title with Sweden's Thomas Kihlstrom 23 years ago.

 

Clark, who is also playing in the semi-finals of the men's doubles with Robert Blair, said the secret to his and Kellogg's success was down to a more relaxed attitude and a new weight-loss programme.

 

"I used to put too much pressure on myself going into tournaments but now I'm just trying to relax and enjoy them," he said.

 

"I've also lost around a stone in weight and that has helped my movement around the court. People said I looked huge on TV during the Commonwealth Games and I began to think I had to lose some weight.

 

"I've started eating more healthily and have cut out the take-aways. Before, when I went shopping I was hungry and would come back with 100 pounds of rubbish but now it is different."

 

An ecstatic Kellogg added: "I would never have believed this could have happened. It's brilliant."