Celtic 2 Dundee United 1 The champagne may not be on ice but at least the hangover has been alleviated.

Celtic, if only temporarily, are on top of the Clydesdale Bank Premier League after a match last night that left a home support drained by tension and could have swept away any lingering hopes that Gordon Strachan might have had of winning his fourth consecutive championship.

Goals by Glenn Loovens and Georgios Samaras gave Celtic the three points. A goal by David Robertson gave them the collective jitters. The champions drooped badly after a first-half performance that seemed designed to sweep away any residual torpor from the defeat at Ibrox.

The brisk, early workout was followed by a second period in which Celtic hung on with the desperation of a bloodied, stumbling boxer. The early Mr Motivator was Scott Brown. He led his side in a series of exercises that stretched and finally forced the United defence to succumb.

Celtic on Saturday lacked penetration and pace. Brown and Aiden McGeady provided this at a Celtic Park that seemed unnaturally quiet early on, perhaps in deference to the collective sore head suffered after a calamitous trip to their rivals.

The champions, though, knuckled down to work. Brown, with his highly individual high-stepping gait, kickstarted his side into an action that produced the inevitable roar from the home support.

Brown's two-game ban has done little to curb his hyper enthusiasm. The Fifer cavorts around the park as if he has to use up excess fuel before attempting an emergency landing. This eventuality was precipitated on one occasion by a Lee Willkie lunge but Brown kept his balance throughout an excellent return.

His pace was accompanied by poise. His presence always brings a buzz of expectation to the Celtic support. His passing supplied two excellent opportunities for Celtic in the first half. Samaras smacked the post with a shot into the ground after Brown had released Scott McDonald. The little Australian was almost the beneficiary of another Brown incursion but wasted the chance.

But Celtic were bright and bubbly. The champions were to go flat but they celebrated early ascendancy with a simple goal. Nakamura swung in a an excellent corner and Loovens, strong and influential at the back throughout, headed home powerfully.

Celtic, with McGeady twice skipping clear of Michael Kovacevic, seemed intent on putting the match to bed. But United gave glimpses of what they would offer in the second half.

Marshalled expertly by Morgaro Gomis, the visitors created a series of chances that offered an element of discomfort. The strong and quick Fran Sandaza forced Artur Boruc to a sharp save to his left and the Polish goalkeeper also had to turn a swirling Gomis corner over the bar. Craig Conway fizzed a shot wide but the champagne moment was to be Celtic's.

They opened the second half with a move that seemed to signal last orders for United. McDonald deftly backheeled to Brown who found Samaras. The Greek's almost nonchalant shot brushed off Wilkie and wrong-footed Lukasz Zaluska.

All over, then? Not quite. United have form in coming back at Celtic. The lead seemed to unnerve and serve as a family-sized Red Bull to the Tangerine troops and Robertson scored sharply at the back post from Conway's cross.

This threatened to be merely the beginning of a new hangover for Celtic. Sandaza outpaced Gary Caldwell but was foiled by Boruc. Gary Keneth miskicked in front of goal.

Substitute Andis Shala headed weakly at the back post. There were decent shots on target: two from Prince Buaben and Gomis as Celtic's promise seemed to evaporate in a cocktail of nervous tension and growing confidence from United.

Celtic's increasing anxiety was marked by the introduction of Paul Hartley. The Scottish internationalist epitomised Celtic's second-half travails. He did not lack effort or determination and crashed into tackles. But his uncertain touch almost launched a United raid that the excellent Loovens staunched with desperation rather than reassuring decisiveness.

All Celtic could offer in return was a move that freed Nakamura inside the box. The Japanese midfielder, though, saw his shot well saved by Zaluska and the tide turned quickly back to Celtic's goal.

There were glimpses that the champions could settle the game in the final moments. Jan Vennegoor of Hesselink, on for Samaras, headed weakly at goal and McGeady also found room on the left but his cross was cut out by a United defence.

McDonald almost squeezed a fatal mistake out of Zaluska who sprinted from goal to kick the ball into the feet of the Australian forward. But the biggest roar was reserved for Broony. He had slipped from the game but roared back in with a typical of drive, determination and defiance.

It summed up a Celtic performance that was blemished with hesitancy but undoubtedly marked with character.

The roar that marked the end of the match could have induced a hangover headache worthy of Oliver Reed. It signalled that Celtic can still hope for a championship celebration.

Gordon Strachan could be forgiven last night for suspending his teetotalism in favour of a strong drink to steady his nerves.