The Wales midfielder converted a James Forrest cross after 16 minutes from close range to extend the Hoops' domestic winning run to 17 games.
Celtic defender Daniel Majstorovic was controversially shown a straight red card by referee Steven McLean on the hour mark before Caley defender Steve Williams was sent off in the 77th minute for picking up a second yellow card for a foul on Georgios Samaras.
Source: PA
