Joe Ledley grabbed the only goal of the game as Celtic leapfrogged Rangers to the summit of the Clydesdale Bank Premier League.
A second-half header from the Welshman proved to be the difference in the second Old Firm derby of the season, although Rangers may argue an early header from Lee Wallace also crossed the line when the match was deadlocked.
The Scottish champions were 15 points clear of Celtic in early November but now find themselves heading into 2012 trailing by two points in the title race.
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