Rangers scored three times in a tremendous second-half comeback to beat Celtic 4-2 at Ibrox and move four points clear of its fierce Glasgow rival atop the Scottish Premier League on Sunday.
The reigning champions were 2-1 behind at halftime but after Croatia striker Nikica Jelavic brought the sides level in the 55th minute, Kyle Lafferty put the hosts ahead from close range in the 67th before Steven Naismith sealed the win in stoppage time.
Naismith had put the hosts in front in the 23rd but Celtic, which had midfielder Charlie Mulgrew sent off for a second yellow card in the 75th, responded with goals by Gary Hooper and Morocco defender Badr El Kaddouri.
Rangers remain unbeaten this season after Ally McCoist celebrated his first Old Firm derby victory as Rangers manager.
''As big a three points as it is, it's only three points,'' McCoist said. ''It's the first Old Firm game of the season and it was a terrific game and I'm a lot happier tonight than Neil (Lennon) and his boys will be.
''But I've been around the block in Old Firm games long enough to know that it's swings and roundabouts. Today's three points were well-earned and they are a big three points - but no more than that.''
Celtic had gone into the break with the advantage thanks to an uncharacteristic error from goalkeeper Allan McGregor, who allowed El Kaddouri's long-range strike to slip through his legs.
''Good goalkeepers maybe do that three or four times in their careers,'' McCoist said. ''If anyone was due a favor it was Allan McGregor as he has been top-class and will continue to be top-class for us.''
