The oilmen saw off repeated attacks from their fancied Kolkata rivals and then scored in the 87th minute through Katsumi after a fine counter-attack to break the hearts of East Bengal players in the Round 15 match at the Ambedkar Stadium here.
With the upset today, ONGC turned out to be the league's giant-killers, having defeated Dempo and drawn against defending champions Salgaocar, big-spending Prayag United and Mohun Bagan, though the last result has been deleted from the record book after the AIFF banned the green and maroons.
ONGC have lost just once in their eight home matches -- the lone defeat being the 2-4 verdict against Air India. They are now on 16 points from 14 matches.
East Bengal, placed third in the league before this match, stay at 27 points from 14 outings. Trevor Morgan's side paid the price of profligacy of their strikers who wasted chances galore, and the defeat may dent their hopes of winning the title.
For East Bengal, who had emerged 5-0 victorious in their first-leg home tie in Kolkata, today's loss was the third of the season.
Incidentally, it was ONGC who had halted East Bengal's winning spree two years ago which had eventually contributed to the Kolkata side falling out of title race.
Katsumi, who was by far the best player on the pitch, broke free in a scintillating solo effort to cut past Arnab Mondal and unleash a powerful right-footer that rocketed past a diving Abhijit Mondal.
The fleet-footed Japanese play-maker's spadework was the highlight of an otherwise lacklustre match.
As expected, East Bengal were on the offensive from the word go. The runners-up of last season knit together a series of attacks forcing ONGC to sit back and defend. MORE
