Yusa Katsumi had put the home side ahead in the 19th minute, which Ghanaian striker Yusif Yakubu cancelled late into injury time (90+3')...
The result takes Mumbai FC seventh on the table, with 31 points from 25 matches, which is the same as Santosh Kashap's side who are eighth due to an inferior head-to-head record with Mumbai FC.
Kailash Patil could have put the home side ahead in the fifth minute, but was caught on the wrong foot by rival defender Kamaljeet Kumar, while Yusa Katsumi sent the resultant free-kick wide.
Another free-kick by David Lalrinmuana went off target before Mumbai FC began to hit on the offensive and almost took the lead in the 12th minute, if not for Sachin Gawas' goal-line clearance to deny Justin Stephen's header off a Nicholas Rodrigues corner from entering the nets.
Kamaljeet's hand-ball in the area from a cross by Lalrinmuana saw the referee point to the spot, and the penalty was converted by Katsumi in the 19th minute.
On the other side, Mumbai FC's Peter Costa set up team-mate Evans Quao, whose shot was just about kept out by ONGC keeper Rehenesh TP in the 31st minute.
Katsumi's substitution in the 35th minute, after the Japanese was seen limping on the ground, brought about the change of fortunes for the away side.
Crossing over, Mumbai FC started dictating terms in the final third but were well dealt by the ONGC stopper-backs on most occasions.
Admist the chances that Jamil's men should have put to rest, John Coutinho wasn't able to get the better of Rehenesh in an one-on-one situation with the ONGC custodian in the 58th minute, while Yakubu directed his header wide from a cross sent in by Rodrigues a few minutes later.
ONGC weren't completely quiet either as Jatin Bisht saw his header come off the post from a Lalrinmuana corner in the 65th minute, while substitute Kuttymani sent his header wide at the other end in the 88th minute.
It was right at the death that Abhishek Yadav set up Yakubu and the veteran striker banged it in to the right of Rehenesh in the 94th minute which saw the game end on a 1-1 scoreline.
The result takes Mumbai FC seventh on the table, equal on points with ONGC FC (8), both of whom have garnered 31 points from 25 matches.
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