Victory pulled the Hoops five points clear of arch rivals Rangers at the top of the table.

Paul Hartley put Celtic ahead on the stroke of half time. Visiting striker David Clarkson was shown a straight red card in the 57th minute for a push in the face of Parkhead substitute Paul Caddis and that left his side facing a real uphill struggle.

McDonald sealed the points by firing in from the edge of the box on 70 minutes.

Rangers will hope to reduce the deficit when they travel to Kilmarnock on Sunday.

Dundee United stay third after a 2-1 win over Aberdeen, whose miserable recent record at Tannadice continued.

The home side were two goals ahead inside the opening 14 minutes following strikes from Francisco Sandaza and Warren Feeney before Darren Mackie gave the Dons hope of a point in the second half.

United are now unbeaten in nine games, with Aberdeen still failing to leave Tayside with a single point since Craig Levein's arrival.

In a key battle at the foot of the table, Hamilton were held 1-1 at home by Falkirk to remain bottom.

Falkirk substitute Michael Higdon headed home just two minutes after his half-time introduction to earn his side a point.

Teenager James McCarthy had put Hamilton ahead 10 minutes before the break.

St Mirren are sandwiched in between Hamilton and Falkirk at the bottom after they lost 1-0 at home to 10-man Hearts.

A 79th-minute header from Eggert Jonsson ended the Edinburgh side's run of five games without defeat.

Hearts had been on the back foot for the majority of the second half after Michael Stewart was shown a red card just before the break for clashing with Hugh Murray.

Inverness pulled out of the bottom three with a 2-1 smash-and-grab win at Hibernian to halt a five-game losing run.

A strike from Don Cowie gave the visitors a shock lead against the run of play on the half-hour mark.

And when Ian Black doubled the Highlanders' advantage two minutes after the break it was too much for an under-par home team to overhaul.

Derek Riordan's stoppage-time strike was nothing more than consolation for Mixu Paatelainen's men.