Celtic overcame a determined Inverness Caledonian Thistle side to remain four points behind Scottish Premier League leaders Rangers.
Gregory Tade had an effort saved by Celtic goalkeeper Fraser Forster before Joe Ledley fired the hosts ahead.
James Forrest added a second on 33 minutes, finishing off a clinical counter attack.
Anthony Stokes should have registered a third and Richie Foran's diving header required a smart save by Forster.
The result means Inverness become detached at the bottom of the division, a point behind Aberdeen and Hibernian.
With Rangers having won at Dunfermline earlier in the day, Celtic knew they had to win to bring the gap back to four.
But it was Inverness who were livelier early on and the Highlanders twice caused problems on Celtic's left-hand side.
First, Gregory Tade ghosted in behind the Celtic defence to latch on to a long ball, but his shot was saved by Forster, who had raced off his line.
Moments later, Foran's low centre was deflected just out of the reach of Nick Ross.
The Celtic defence of Daniel Majstorovic and Glenn Loovens looked uncomfortable when Inverness came forward at pace and it took the hosts a while to find their rhythm.
But Ledley lifted the home crowd when he took an excellent first touch off Beram Kayal's pass, pushed forward and drilled a low shot inside Ryan Esson's right-hand post.
Celtic were soon two ahead after a terrific counter attack. An Inverness corner was cleared and Ki Sung-Yueng's incisive pass from halfway put Forrest through on goal, the winger finishing well past Esson.
Greg Tansey had two attempts for the visitors before half-time, but neither troubled Forster.
The pace of the game dropped after the break, Celtic comfortable in possession for long spells.
Forrest and Gary Hooper combined to set up Anthony Stokes in the six-yard box.
But, with only the keeper to beat, the striker lifted his effort high over the bar.
Mohamed Bangura took the place of Hooper and the physicality of the Sierra Leone striker created some nervous moments for the Inverness backline.
The visitors carved out an excellent chance when Graeme Shinne crossed for the diving Foran and Forster reacted well to claw the ball over.
With that, the Highlanders' chances of salvaging something from the game ended as Celtic saw out their win.