India No. 1 Prakash Amritraj and compatriots Vijay Kannan and Saurab Singh crashed out of the ATP Challenger in Belgaum on Wednesday, even as Rohan Bopanna advanced to the pre-quarter-finals.

Twenty-year-old Amritraj, ranked 277, went down fighting 6-3, 3-6, 5-7 to Chinese Taipei qualifier Ti Chen.

The host country suffered another setback when Kannan, a qualfier, bowed out, losing 4-6, 3-6 to unseeded Yuri Schukin of Russia.

However, Bopanna demolished compatriot and wild-card Somdev Dev Varman 6-2, 6-0 to move into the last 16, where he was joined by top seeded Thai Danai Udomchoke and seventh seeded Vadim Kutsenko of Uzbekistan.

Udomochoke defeated Ukranian Orest Tereshchuk 3-6, 6-3, 6-0, while Kutsenko ousted wild card Saurab Singh 6-2, 6-2.

Joining the casualty list were second seeded Yeu-Tzuoo Wang (Taipei), fifth seeded Philipp Kohlschreiber (Germany) and sixth seeded Guillermo Garcia-Lopez (Spain). Wang retired after Germany's Dieter Kindlmann was leading 6-2, 2-1; Russian Dmitry Vlasov whipped Kohlschreiber 6-3, 6-0, while Teimuraz Gabashvili (Russia) downed Garcia-Lopez 6-3, 7-6 (7-3).

Amritraj had himself to blame for the defeat as he grew erratic after a promising start. Having blown away his opponent in a storm of powerful serves in the first set, Prakash took a 2-0 lead in the second, but allowed things to drift away after that.

Chen, who had till then done nothing exemplary, rose to the occasion, and shifted gears to carve out victory.

Earlier, Chen rarely got his first serve in, and in the eighth game double-faulted to set Amritraj for a break point. A blistering forehand return from Amritraj, and a return into the net by Chen gave the Indian the break.

Another double-fault in the first game of the second set put Amritraj a break up. But, by the fourth game, the rot crept in. Amritraj's returns were packed with too much power and his accuracy got a beating. His serves too turned erratic.

"I was very sluggish in the second set," Amritraj admitted. "I held back a bit more than I normally do."

Chen broke him in the sixth and eighth games to level set scores. A bout of cramps in the 11th game of the third set only hastened the end of Amritraj's campaign. Chen lined up three break points in the 11th game and retained serve in the 12th to walk-off victorious.

Other results (all first round): Lee Childs (Britain) bt Norikazu Sugiyama (Japan) 6-4, 3-6, 6-4; Toshihide Matsui (Japan) bt Paul Logtens (The Netherlands) 6-2, 7-6 (7-4).

Doubles: Mustafa Ghouse (India)/Vishal Uppal (India) w/o Guillarmo Garcia-Lopez (Spain)/Norikazu Sugiyama (Japan); Marcello Craca (Germany)/Dieter Kindlmann (German) bt Somdev Dev Varman (India)/Vinod Sridhar (India) 6-2, 6-3; Michal Mertinak (Slovakia)/Branislov Sekac (Slovakia) bt Harsh Mankad (India)/Aisam-Ul-Haq Qureshi (Pakistan) 6-3, 7-6 (7-3); Sonchat Ratiwatana (Thailand)/Sonchai Ratiwatana (Thailand) w/o Ti Chen (Taipei)/Yeu-Tzuoo Wang (Thailand).