Rohan Bopanna conceded his singles semi-final to Pakistan's Aisam Qureshi after taking ill during the match, at the US $25000 Nottingham Challenger on Friday.

Top seed Qureshi was leading 4-3 in the first set when the sixth seeded Indian decided to withdraw.

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"He was not feeling well. It is a stomach problem. A doctor examined him and it does not seem anything serious," a tournament official told rediff.com.

Bopanna, who had beaten the Pakistani ace last week at the same stage in the Manchester Challenger, is expected to partner Qureshi in the semi-finals of the doubles event later in the day.

The third seeded duo, champions in Manchester, will clash with top seeds duo of Harel Levy of Israel and Lars Burgsmuller of Germany [Images]. They had beaten Olivier Charroin and Thomas Oger of France [Images] winning 6-3, 6-7(5), 10-8 in the quarter-finals.

Perhaps, the marathon match may have taken its toll on Bopanna.