Celtic climbed back to the top of the Clydesdale Bank Premier League after a nervy win over spirited Dundee United at Parkhead.

A first-half header from defender Glenn Loovens and a deflected Georgios Samaras strike seven minutes after the break had appeared to take the game beyond the Tannadice men who had, at times, out-passed the champions.

However, Craig Levein's side showed commendable spirit and David Robertson's strike after 57 minutes ensured a tension-filled end to the game.

But the champions hung on, doggedly at times, and are now a point ahead of rivals Rangers — who play Hibernian at Easter Road tomorrow night.

It was United who started the game with confidence and in the fourth minute busy midfielder Craig Conway took a pass from Francisco Sandaza and flashed a shot from 25 yards just past the post.

United dominated possession, playing some neat football but in the 13th minute Celtic midfielder Scott Brown, back after a two-game ban, drove forward before sending Scott McDonald scurrying down the right.

When the Parkhead striker's cross came, Samaras' left-footed shot bounced in to the ground and past United goalkeeper Lukasz Zaluska — only to hit the post before it was cleared away to safety.

United refused to waver and in the 20th minute Conway flighted a cross to the back post and Sandaza's header was netbound before it was brilliantly clawed away by Artur Boruc.

However, a minute later Celtic forged ahead through Loovens after United skipper Lee Wilkie had conceded a corner defending an Andreas Hinkel cross.

Shunsuke Nakamura flighted the ball into a busy six-yard box and the big Dutchman rose highest to flick the ball past Zaluska.

The Taysiders, to their credit, tried to pass their way back into the game but Celtic refused to let them settle and in the 39th minute it needed Wilkie's intervention to prevent McDonald latching onto a Samaras cross at the near post.

The game seemed over in the 52nd minute when Samaras made it 2-0 with a fortuitous goal.

Brown combined with McDonald to set up the Greece international 20 yards from goal but his shot initially appeared harmless until it took a clear deflection off Wilkie to wrong-foot Zaluska.

In the 55th minute, with United in disarray, Zaluska had to make a decent save from Brown's header after the Scotland midfielder had latched onto a sweeping Naylor cross.

But two minutes later Robertson reduced the lead when he appeared at the far post to despatch Paul Dixon's deep cross past Boruc.

As Celtic and their fans began to panic, United midfielder Prince Buaben blasted the ball high over the bar from 14 yards after Robertson's cross had eluded the Parkhead defence.

As tension mounted further, Zaluska pulled off a great save from Nakamura.