Rangers took a massive step towards the Clydesdale Bank Premier League title when they clinched victory in the final Old Firm derby of the season.

Steven Davis proved to be the difference between the two teams when he grabbed the only goal of the game at Ibrox.

The victory could prove pivotal in the title race as Rangers move two points ahead of Celtic into pole position with just three games remaining.

Andrius Velicka's four goals in the last four games were not enough to earn him a start and he was dropped to the substitutes' bench to accommodate the introduction of Kenny Miller, who started up front with Kris Boyd.

Madjid Bougherra returned from suspension to reclaim his usual spot at the heart of defence at the expense of Lee McCulloch, while Maurice Edu remained in the side to make his debut in the famous fixture.

There was a surprise in the Celtic line-up with Aiden McGeady dropped to the bench in favour of Shaun Maloney, whose last start for the Hoops was against Queen's Park in the Homecoming Scottish Cup.

A stomach muscle problem meant Lee Naylor was also named among the substitutes. He was replaced by Darren O'Dea at left-back, while Glenn Loovens filled in for injured skipper Stephen McManus at centre-back.

Davis attempted to give Rangers an early advantage with a shot from distance which flashed across the face of goal and wide without really troubling Artur Boruc in the Celtic goal.

Miller then connected with a Christian Dailly cross from the right but his overhead kick was also off-target.

At the other end, Celtic had the opportunity to put their hosts under pressure when they earned a free-kick just outside the box for a David Weir foul on Scott McDonald.

Shunsuke Nakamura presided over the set-piece and a well struck, curling effort was tipped just over the crossbar by Rangers goalkeeper Neil Alexander.

If that chance was close, Steven Whittaker then drew gasps from the Ibrox crowd with a cross intended for Davis which eluded everyone in the box before smacking off the far post.

Celtic were furious with 32 minutes gone when McDonald went to ground under pressure from Whittaker as he was about to unleash the shot and referee Craig Thomson ignored the pleas for a penalty.

Five minutes later, Rangers surged into the lead. Boyd slipped a pass through to Miller who whipped the ball into the goalmouth for Davis to slide into the back of the net from inside the six-yard box.

There was concern for the home side just before the break when Edu crumpled to the turf after apparently suffering a late challenge from Loovens but, despite initially looking like his game was over, he was able to return to the action.

Celtic then had a great chance to restore parity before the half-time whistle but Davis' contribution at the other end proved to be just as significant when he cleared a Jan Vennegoor of Hesselink header off the line.

The big Dutchman had a chance to make amends in the second half when he threw himself in front of an Andreas Hinkel cross only to see his header smothered by Alexander this time.

A major criticism of Boyd's game has been his lack of goals against Celtic - he had netted just once in 18 career appearances before this game - and he squandered another great opportunity.

The striker ran onto a lovely ball from Miller, raced into the box, and squeezed between two hooped jerseys only to fire straight at Boruc, who managed to block the point-blank shot.

McGeady was thrown into the action for Maloney with just over an hour gone and was not too far away with a blistering drive which was narrowly off-target as the champions desperately tried to haul themselves back into the game.

Boyd could have sealed the win with five minutes to go but nodded over after again being set up by Miller but Rangers managed to hold on for the win which puts them in the driving seat.

Teams:

Rangers Alexander, Dailly, Bougherra, Weir, Whittaker, Davis, Mendes, Edu, Steven Smith (Lafferty 69), Boyd (McCulloch 85), Miller.

Subs Not Used: McGregor, Novo, Velicka, Fleck, Wilson.

Booked: Steven Smith, Miller, Lafferty.

Goals: Davis 37.

Celtic Boruc, Hinkel, Loovens, Caldwell, O'Dea (Naylor 81), Nakamura, Hartley, Crosas, Maloney (McGeady 62), Vennegoor of Hesselink (Samaras 76), McDonald.

Subs Not Used: Mark Brown, Misun, Flood, Robson.

Booked: Hartley, Caldwell, Naylor.

Att: 50,321

Ref: C Thomson (Scotland).