Mohun Bagan maintained their unbeaten record after a goalless draw against Thailand club Osotspa M-150 in the Group F encounter of the AFC Cup football tournament, in Bangkok, on Tuesday.

With this draw, the Kolkata giants have five points from three outings, having beaten Pahang of Malaysia 2-1 in an away match and drawn with Tampine Rovers of Singapore 0-0 in Kolkata.

Osotspa have four points from three matches while Tampine Rovers are with four points from two matches in the four-team group. Pahang have yet to open their account.

Six Group winners, one best runner-up from Group A, B and C and one best runner-up from Group D, E and F qualify for the quarter-final stage of the competition.

The Thai side, which went into the game looking to bounce back from their 2-1 defeat to Tampines Rovers in their previous outing, dominated for most part of the match but failed to find the winning goal.

Bagan signalled their attacking intentions right from the start with a three-pronged attack of skipper Jose Barreto, Lalawmpuia and star striker Baichung Bhutia, but found the going tough on a Royal Thai Army stadium pitch that was churning up badly following an early afternoon downpour.

However, despite Bagan's domination early, Osotspa soon gained ascendancy in the first half with some skilful play that belied the heavy pitch.

In the first session, Osotspa had two half chances. First Ponlawat Wangkahad's angled drive was kept out by Bagan 'keeper Shilton Paul and later defender Sanjeev Maria blocked a stinging Jakkrit Bunkham drive that may have broken the deadlock.

The Thai side, which finished second in the 2006 league, continued their dominance in the second session also and Jakkrit quickly came close to redeeming himself on two occasions.

In the 56th minute, Jakkrit's curling shot went just wide off the mark and then, in the 62nd minute, he hit a sweetly struck volley that dipped over the Mohun Bagan bar.

The green and maroon Kolkata outfit seemed bereft of ideas but they were almost gifted the lead late in the second half against the run of play when a cross-shot from Bhutia squirmed through the hands of Thai goalkeeper Narong and onto the roof of the net during a rare foray into the Osotspa half.