The striker scored the first goal as we dragged ourselves back from 2-0 down against the Premier League leaders at the Etihad Stadium.
Gareth Bale curled home a beauty for 2-2 and we looked the more likely to win in the final 20 minutes.
Then, as the clock ticked into the first of four minutes added time, Jake Livermore sent Gareth away down the left.
Gareth sped past Joleon Lescott and squared for Jermain, who was clear in front of goal but couldn't quite reach the ball enough to turn it into the empty net.
The agony was piled on minutes later when City won a penalty and with 94 minutes up, Mario Balotelli slotted home the winner.
"As soon as I made the run I thought it was a goal," said Jermain.
"I had to stretch, reach the ball and hook it back, but I couldn't quite reach it.
"Even then I thought we’d get the point and that the lads had done brilliantly, but the last-minute penalty followed and it was all over.
"There were a lot of positives to take out of it. It was an unbelievable performance and the lads were devastated. Not many teams will go to City and perform how we did.
"We’ll keep going, we’ve big games coming up and I think they are games we can win."
Jermain's strike made it 12 for the season in all competitions and lifted him up another place in the club's all-time goalscoring list with 113 goals.
It took him above Jimmy Dimmock - FA Cup Final match-winner back in 1921 - who scored 112.
A place in the top 10 is his next target and he needs five more to overhaul Les Bennett, who scored 117 times for us in 294 games.