New Delhi, Sep 16 - Riding on a brace each from Surkumar Singh and Edeh Chidi, Mohun Bagan demolished ONGC 5-1 in their opening quarter final league match of the 122nd Durand Cup football tournament here Wednesday.

Fresh from their IFA Shield final loss to Churchill Brothers, Mohun Bagan put on a clinical performance to stake claim to their 17th Durand Cup title at the Ambedkar Stadium.

The Green and Maroon brigade from Kolkata could have won by a bigger margin, but Jose Barreto missed a penalty. The Brazilian, however, atoned for it in the 43rd minute by scoring a brilliant goal in the group two match of the tournament.

Mohun Bagan dominated the proceedings right from the start as Chidi and Barreto combined well to rattle the ONGC defence. For ONGC, nothing went their way and their striker Baba Tunde and Lalsangzuala didn't get much support from the half-line. Tunde, however, managed to score the solitary goal in the 82nd minute.

The 16-time champions went ahead in the ninth minute after an unmarked Surkumar hit from a rebound off James Singh's perfect flag-kick.

Nigerian Chidi came close to double the lead in the very next minute but missed the sitter after being set up by James.