Bhupathi and Knowles broke Paes in the second game of the first set. However, the lead was shortlived, with Knowles getting broken for 2-2. At the ensuing changeover, Paes needed attention from the trainer.

Paes dropped his serve again in the sixth game and Knowles consolidated the break by holding his serve for a 5-2 lead. Bhupathi then served out the first set.

'I didn't hold serve once in the whole first set,' Paes said. 'I was struggling to win points.'

Bhupathi and Knowles, who teamed up in 2008, carried the momentum early in the second set. Dlouhy appeared to be coasting on serve, up 40-15 in the first game. But Bhupathi and Knowles won the next three points, and a superb backhand return by Bhupathi helped set up the break.

When Bhupathi held at love, making it eight straight points, it seemed to be all over for Paes and Dlouhy, especially when the Indian double-faulted to begin the third game.

But Paes held and then they broke to go up 3-2.

Paes flashed his brilliant return game, slicing backhands cross-court and floating forehands down the line. Four break points came and went, but on the fifth, Bhupathi cracked.

The seesaw battle continued, Paes broken to love, only for Knowles to drop serve on a missed backhand volley by Bhupathi.

In the third set, Dlouhy and Paes broke their opponents twice.

Bhupathi and Knowles had their last real chance in the fourth game on the susceptible Paes serve. Manufacturing three break points, Bhupathi missed a comfortable forehand on one and a routine backhand on another.

Paes couldn't hide his delight seconds after converting the match point, jumping into the arms of Dlouhy.

Bhupathi and Knowles, both former No. 1 in doubles, are still waiting for their first major together. Sunday's defeat looked similar to their loss in the Australian Open final, when they led the Bryan brothers by a set but couldn't apply the knockout punch.

But as Bhupathi pointed out, maybe the duo was lucky simply to get this far. Knowles, like Paes, was wounded, playing with stitches on his finger. He cut the finger after holding open an elevator last week.

In the junior section, top seeded Indian Yuki Bhambri bowed out after losing to American Chase Buchanan 3-6, 6-7 (4) in the quarterfinals.