- Rangers score three second half goals to beat Celtic in Glasgow's Old Firm Derby
- Steven Naismith on target in each half for Rangers who go four points clear at top in Scotland
- Celtic have Charlie Mulgrew sent off in the second half for second bookable foul
- Old Firm Derby is one of the most hotly-contested in world football
Rangers scored three second-half goals to beat Celtic 4-2 in Glasgow's Old Firm Derby Sunday and go four points clear in the Scottish Premier League.
In-form Steven Naismith fired Rangers ahead with a thumping strike after 22nd minutes but Celtic were quick to level through Gary Hooper's well-worked goal 12 minutes later.
Celtic took the lead just before halftime as Rangers goalkeeper Allan McGregor allowed a weak shot from Moroccan Badr El Kaddouri to elude his grasp and trickle into the net.
But Nikica Jelavic headed Rangers level seven minutes after the interval and they were ahead when Kyle Lafferty converted after 67 minutes.
Mulgrew, who was fortunate to escape with just a yellow card for his first half challenge, then saw red in the 75th minute and Naismith took advantage against 10 men to score the fourth and his second in injury time.
"I didn't think there was an awful lot between the teams in the first-half. I'm not sure we deserved to go in 2-1 down but that's what we were faced with," Rangers manager Ally McCoist told Sky Sports.
"We asked the boys for a reaction in the second-half and boy did we get it."
Celtic manager Neil Lennon was disappointed by his team's second half display: "We didn't compete and it was almost as if the players had gone out in the second-half thinking the game was won," he said.
Matches between the two giants of Scottish football usually prove crucial in the domestic title race and the victory left Rangers on 19 points after seven games, with Celtic on 15 in second.