British duo Nathan Robertson and Jenny Wallwork have boosted their Olympic qualification hopes by beating GB rivals Chris Adcock and Imogen Bankier.
Robertson and Wallwork defeated Adcock and Bankier, the top-ranked GB pair, 14-21 21-17 21-8 in the first round of the Malaysian Open.
It was the first time the two pairings had met competitively.
Robertson and Wallwork will play Indonesia's Danny Bawa Chrisnanta and Yu Yan Vanessa Yeo on Thursday.
GB MIXED WORLD RANKINGS
- 16th - Adcock (Eng) & Bankier (Sco)
- 18th - Blair (Sco) & White (Eng)
- 23rd - Robertson (Eng) & Wallwork (Eng)
Victory over Adock and Bankier will boost Robertson and Wallwork's flagging hopes of qualifying for this summer's Games, with only the highest-ranked British pair guaranteed a place unless the second-ranked duo are in the world's top eight.
Adock and Bankier are currently ranked 16th in the world, with Robertson and Wallwork in 23rd behind Gabby White and Robert Blair in 18th.
Wallwork returned to the court for the women's doubles with Gabby White but the Leeds pair lost to Korean second seeds Ha Jung Eun and Kim Min Jung 21-9 21-18.
White and Blair are in action against fourth seeds Tontowi Ahmad and Liliyana Natsir of Indonesia on Wednesday, whilst men's doubles Adcock and Andrew Ellis face third seeds Biao Chai and Guo Zhendong of China.
Britain's top men's singles player Rajiv Ouseph takes on Chinese third seed Long Chen.