Ayew scored the second goal that drew Marseille level before they went on to win win 3-2 with a Matthieu Valbuena goal.
"It was very pleasing and it proved that we're men, that we're determined and never give up," said Ayew after leaving the jubilant Marseille dressing-room.
"At 2-1, we knew we still had a chance. We tried to score again quickly after the break; we didn't quite manage it, but I was fortunate enough to score from a corner to make it 2-2. After that, we told ourselves we had nothing to lose, and that we had to go for it and create a surprise.
"We didn't give up and we showed that the game isn't over until the referee blows his whistle.
"We were very happy when the third goal went in, but the match wasn't finished yet," he explained.
"We'd come a long way, but we owed it to ourselves to put in a huge defensive effort to keep our lead and go through. It's a match that will live long in the memory, and even longer if we can continue through to the quarter-finals."