Leander Paes and his Czech partner Lukas Dlouhy's chances of making the knockout stage of the ATP World Tour Finals' doubles event suffered a jolt after they were handed a straight-set defeat by debutants Lukasz Kubot and Oliver Marach in their opening Group B match in London on Monday.
In a 92-minute contest, both the teams fought hard with many players taking body blows - including one in the throat for the 36-year-old Paes.
But in the end, it was the sixth-seeded pair who came out on top, having saved five of six threats on their serve and converted two of the four break points they created.
Dlouhy was targetted by Kubot and Marach in the tie-break and a barrage of shots from the back saw the Czech player break down at the net to give the Polish-Austrian duo a 6-3, lead. The sixth seeds then converted their first match point as Dlouhy returned the serve long.
"I can't really speak for the other top teams that have lost, but I can speak for us. We just didn't play our best game today," Paes said.
"We had a bunch of chances, especially in the second set. We had a bunch of chances to break. I think it was four or five break points.We didn't take it. We weren't good enough for the mark. Also you have to give credit to the other boys.
"They came out and brought the game to us. We knew their weaknesses, we knew their strengths. But they managed to play well enough to beat us today," he added.
Paes and Dlouhy have to be among the top two in the group to make the cut for the knockout stage.
Paes and Dlouhy, who were bidding for their 50th career victory together on Monday, have been in good form. In just 15 tournaments this season, they have won two Grand Slam titles at Roland Garros and the US Open and finished runners-up at the World Tennis Tournament in Rotterdam.
Mahesh Bhupathi and his Bahamian partner Mark Knowles, seeded third in group A, had won their opening match on Sunday.
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