The Spaniard went into the game with just one goal this season but trebled his tally with both in a 2-0 win.
Roberto Mancini's assistant said: "Last year he had a few more goals under his belt but we know how important he is whether he is scoring goals or not.
"I think his performances have been right up there. I think it would be harsh to say it has been lacking. He is in the team for all sorts of different reasons, not just his goalscoring ability.
"I think his performances of late have deserved goals. I am pleased he got the two and he should have had a third."
City - temporarily, at least - moved to within four points of leaders Manchester United, and Platt said: "We have got 15 games left. Both teams will drop points, I am sure.
"We have got to make sure we keep getting victories so if United slip up we are in a position to take advantage of that."
City lost Pablo Zabaleta to an ankle injury, but Platt said: "I would be surprised if he was out for next week."