Kolkata: Vafa Hakhamaneshi scored the solitary goal in Chennaiyin FC's victory over East Bengal in the Indian Super League here on Friday.
The Iranian, who had received a yellow card earlier, was sent off following a second yellow for his celebration of the 69th minute goal. Shortly afterwards, East Bengal's Sarthak Golui was also sent off.
East Bengal were unchanged while Chennaiyin missed out Kwame Karikari with an injury but welcomed back Debjit Majumder in goal.
O'Doherty had an early chance to put the hosts ahead but found his shot blocked. Petar Sliskovic, meanwhile, hit the post at the other end to the relief of the home crowd.
East Bengal's Malayali striker VP Suhair fired wide from a counter while Chennaiyin skipper Anirudh Thapa was kept out by Kamaljit Singh.
Both sides had their chances that weren't taken. But Hakhamaneshi couldn't miss an easy finish from an Akash Sangwan corner.
Chennaiyin have moved up to 5th position with seven points while East Bengal have fallen behind Kerala Blasters, into the 10th position after their fourth defeat in five matches.
(With agency inputs)