Nainggolan is booked for kicking the ball away as City win a free kick 50 yards from goal on the right wing.
David Silva cleverly works space after bringing down a high ball outside the box, and drags a left-footed shot just wide of goal.
Juan Iturbe replaces Francesco Totti as Roma maintain their attacking intent.
As is tradition, Lampard has a shot from outside the box, but it falls just outside the post and the 'keeper takes no chances, pushing the ball away.
The ball runs to Pjanic, lurking on the edge of the box, but he lashes a rising shot well wide of goal. City are on top at the moment. Elsewhere, Chelsea are still 1-0 up at Sporting Lisbon, and PSG lead Barcelona 3-2.
The young defender is booked for coming in from behind on Sergio Aguero. City have a free kick from 35 yards, with Skorupski claims.
Seydou Keita comes across to take the ball off Fernandinho as he rushes into the box to chase a return ball.