India's Leander Paes and Mahesh Bhupathi have entered the semifinals of the Barclays ATP World Tour finals doubles, defeating top seeds and three-time winners the Bryan twins, Bob and Mike, 6-4, 6-2.
Had the Bryans -- who had already qualified after winning the first two round-robin matches - beat Paes and Bhupathi in straight sets, then seventh seeds Austrian Jurgen Melzer and his German partner Philipp Petzschner would have qualified for the semifinals.
The Indian pair will face Poland's Mariusz Fyrstenberg and Marcin Matkowski in the semifinals on Saturday.
In the other semifinal, the Bryan brothers play Max Mirnyi of Belarus and Canadian Daniel Nestor, who topped Group B beating among others India's Rohan Bopanna and his Pakistani partner Aisam-Ul-Haq Qureshi, who have played in the Tour finals for the first time.
Earlier in the day, Melzer and Petzschner beat sixth seeds Swede Robert Lindstedt and Romanian Horia Tecau 6-3, 6-4.
It was an unexpectedly easy victory for the fourth-seeded Indians over the World No 1 pair at Arena O2 here Friday and the victory gave them the top spot in Group A with two victories and one defeat. Bryans finished second.
Bhupathi and Paes -- losing finalists to Americans Rick Leach and Jonathan Stark in 1997, to another American pair Sebastien Lareau and Alex O'Brien in 1999 and to American Daniel Johnson and South African Piet Norval in 2000 - won the match in a shade less than an hour.
Bhupathi and Paes, who have decided to split after this tournament, produced their best tennis when it mattered most.
The Indians beat the Bryans when they last met at the Cincinnati Masters earlier in the year, had an early break and that was enough for them to take the first set.
The Bryan brothers, who have just finished at the top of the doubles rankings for a record seventh time in nine years, were sluggish and struggled to stay in the hunt. Another quick break and the match was gone for the Americans.
Bhupathi and Paes are playing together in the end-of-season event for the first time in a decade after reviving their successful partnership which dominated the doubles play in the 1990s.
Bopanna and Qureshi, who lost all their three matches to finish at the bottom of the Group B standings, have also decided to end the successful tie-up with the Indian partnering Bhupathi at the Chennai Open next month.