Playing with fierce determination, India's Harsh Mankad stormed into the semi-finals of the Indian Oil Servo ATP Challenger in Bangalore on Thursday.

Continuing his fine run in the tournament, the 23-year-old from Mumbai came from behind to beat qualifier Fred Hemmes Jr of The Netherlands 6-7 (3-7), 6-3, 6-3.

Mankad, ranked 457 in the world and also a wild card entrant in the tournament, was a bit tentative in the first set but came back strongly in the next two, to emerge a deserving winner.

He was joined in the last four by second seed Gregory Carraz of France and fourth seed Ivo Heuberger of Switzerland.

Carraz had no difficulty in packing off Peter Wessels of the Netherlands 6-2, 6-3.

In another quarter-final, Heuberger registered a 6-3, 6-1 win over South African Louis Vosloo.

In the Mankad-Hemmes Jr match, the Indian started in whirlwind fashion, racing to a 4-0 lead in the first set, but then suddenly found himself losing direction as he made a series of unforced errors.

Taking advantage of the lapse, Hemmes Jr. clawed his way back and won the set via the tie-breaker with ease.

But that was as far as he could get, as Mankad played a steady game from the baseline and kept his opponent guessing by making him move around the court with passing shots down both flanks. The Dutchman grew erratic and Mankad seized the opportunity and proceded to score a memorable victory.

In the semi-finals tomorrow, Mankad will take on second seeded Frenchman Gregory Carraz.

Fourth seed Ivo Heuberger of Switzerland and eighth seed Gilles Elseneer of Belgium will cross swords in the other semi-final.

Elseneer advanced, defeating Yves Allegro of Switzerland 6-4, 3-6, 6-3.

Results: (All Indians unless otherwise specified)

Doubles: (quarter-finals): Noam Okun (Israel)/Arvind Parmar (Britain) bt Massimo Dell'acqua/Frederico Luzzi (both Italy) 6-3, 6-4; Prakash Amritraj/Rohan Bopanna w/o Jonathan Erlich (Israel)/Fred Hemmes Jr (the Netherlands); Rodolphe Cadart/Gregory Carraz (both France) bt Yuri Schukin/Dmitry Vlasov (both Russia) 6-3, 6-4.