City defeated United 3-1 in the first-leg of their semifinal.
“I enjoyed the role because we won and particularly because it worked," he said.
“Pep (Guardiola) wanted more men in the middle and that's why he put me there and happily things went our way.
“It's never easy to come here against one of the best sides in England and Europe and win 3-1 but we did it.
“We were disappointed to lose against United last month because it is not normal for us to lose at home and I hope this makes up for it to our fans."