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Celtic proved themselves worthy champions with a convincing win over the troubled, administration-hit Rangers side they deposed.

Rangers had started brightly, but they looked a dispirited bunch from the moment Charlie Mulgrew dived unmarked to head Celtic into a 17th-minute lead.

Kris Commons chipped over goalkeeper Allan McGregor on the break to extend the lead on 31 minutes.

And Gary Hooper blasted in from distance nine minutes after the break.

Celtic's fans taunted their Rangers counterparts over the prospect of liquidation

The victory in the final Old Firm derby of the season stretches Celtic's lead over their Glasgow rivals to 21 points with three games remaining to emphasise that the team from the East End would have won the title even if Rangers had not been docked 10 points for going into administration.

Ally McCoist's side left the field looking shellshocked and with the taunts of the Celtic fans ringing in their ears amid banners and chants suggesting that this might be the last-ever Old Firm derby should Rangers go out of business.

Celtic manager Neil Lennon had ditched the experimental line-up that defeated Motherwell last weekend and brought back the experienced Fraser Forster, Adam Matthews, Glenn Loovens, Georgios Samaras and captain Scott Brown.

But Rangers, unchanged from the side that defeated Hearts to record their fourth straight win and looking to repeat last month's 3-2 win over Celtic, started confidently, with Lee McCulloch sending a 22-yard volley a couple of yards over after a neat Andy Little knock-down.

Play was already swinging from end to end and Kris Commons mis-hit a 16-yard drive after an Emilio Izaguirre cross caused panic in the Rangers defence.

Rhys McCabe had a long-range effort deflected just wide of a Celtic post before leading a breakaway that ended with a Little shot straight at goalkeeper Forster.

However, Celtic took the lead with their first corner, which was driven long by Commons to the head of Mulgrew.

The player of the year candidate arrived late and unmarked to head down off the turf and into the roof of the net past McGregor from 15 yards.

Having taken heart from the opening goal, Celtic started to look the more incisive and extended their lead through Commons.

Gary Hooper gathered the ball out wide and, when the striker found Commons with a low crossfield pass, the winger nutmegged Kyle Bartley before chipping over the advancing McGregor.

Rangers were now on the rocks, unable to cope with Celtic's fluid system after Lennon switched to three at the back, and McGregor had to beat away a powerful Victor Wanyama drive.

The second half continued in the same manner, with McGregor being forced into a superb fingertip save to turn a Joe Ledley drive over the crossbar.

McGregor had to save smartly on his goalline following Wanyama's mis-hit effort from the resulting corner, but the goalkeeper was given no chance when Celtic extended their lead moments later.

McCabe was dispossessed by Commons and Samaras' quick pass found Hooper with plenty of space to find the top corner with a rasping drive from 20 yards.

It was the 73rd minute before Rangers had another effort on goal, with substitute Salim Kerkar's chip sailing harmlessly over the crossbar.

Hapless on-loan Arsenal defender Kyle Bartley's frustration boiled over with a couple of dangerous tackles that ought to have been more harshly dealt with than the yellow card shown for the second that flattened Izaguirre.

Forster pushed wide a powerful curling free-kick from Sone Aluko and Brown was lucky not to be sent off for a thumping challenge on Kerkar.

By then, however, the game was over as a contest as the two sets of fans rocked the stadium, one set in celebration, the other with a defiance largely absent from their side on the field of play.