KILMARNOCK continued their excellent start to the season by leap-frogging champions Celtic and early season pace-setters Inverness Caledonian Thistle to move into the top three at the expense of the surprisingly lacklustre leaders last night.

The only real disappointments for the home club on the night were that fewer than 4000 were at Rugby Park for a match between two teams that have been going so well, and that first-choice goalkeeper Craig Samson had to be replaced at half-time after suffering a broken toe that may keep him sidelined for six weeks.

However, manager Allan Johnston said he would have no qualms over having to play youngster Connor Brennan in the interim on the basis of his second-half performance and declared himself delighted with the overall display. "I thought we started really well and dominated the majority of the game," he said. "United are a quality team and they had their spell but I always thought we were the more dangerous."

Jackie McNamara, his counterpart at United, was disappointed with the way his men had spurned their chance to take a commanding lead at the top of the table. "We took about half an hour to settle in. You would think we were nearer the bottom of the league than the top with our distribution tonight," he said.

Josh Magennis led the line impressively for his side throughout, testing Radoslaw Cierzniak with an angled shot and then forcing the goalkeeper into a fine reaction save from a powerful downward header in the early exchanges. The home side then created another excellent opportunity when Ross Barbour rose beyond the far post to meet a corner from the right and directed it into the path of Tope Obadeyi around eight yards out, but he rushed his effort and blasted the ball high over the bar.

Kilmarnock had made the livelier start, but the league leaders began to assert themselves without producing anything particularly menacing. The best chance fell to Armstrong when, in pursuit of Chris Erskine's through ball towards the penalty spot, he squirmed past Mark Connolly's challenge and into the out-rushing Samson but the United player came off second best in the collision.

The visitors were then almost caught out by the surface. Callum Morris misjudged a bouncing ball just outside the box - he thought it was going to skid on to his goal-keeper but instead hopped up awkwardly. As Cierzniak came out, Magennis got his foot to the ball and lobbed it over him, but the artificial pitch then levelled things out when the ball lifted higher than expected and landed on top of the bar.

Within a minute Morris came close at the other end when he had a header half-blocked from a corner on the left then hooked the rebound over the bar.

However, it was the home team that ended the half the better. Alexei Eremenko sent a curling shot just over from wide on the left before his well struck attempt from a free kick 30 yards out almost caught Cierzniak out after Magennis tried and failed to get a touch on it.

The second half began cagily, 11 minutes elapsing before the first incident of any sort of note. That was when Magennis looked favourite to get to Eremenko's high early cross into the box only to feel he was illegally impeded by Morris. The referee Crawford Allan was not interested, but Kilmarnock claimed the lead they deserved with a delightfully crafted goal just after the hour.

Eremenko looked to have been closed down by Dillon as he got to the byeline wide on the right, however he flicked it round him with a neat piece of skill, then slid the ball to Obadeyi inside the box. He might have shot first time, but took a touch and slipped the ball past Paul Paton, then kept his composure to roll it with his left foot past Cierzniak as he raced off his line.

Having taken 63 minutes to break the deadlock the hosts struck again within another three, albeit it was a more prosaic strike this time. Eremenko's corner from the left was met solidly by Connolly, who put it beyond Cierzniak to his right.

United had brought Gary Mackay-Steven on between the goals and he came close to reducing the deficit when he found space on the left inside the box to get in a left-footed shot but the ball skimmed just over.

The leaders were then offered a gilt-edged chance when a miscued pass back sent Erskine racing into the box on the right but his drive was parried by Samson and while Ola Adeyemo, who had replaced the unusually ineffective Nadir Ciftci a few minutes earlier, got to the rebound first the youngster skewed his effort so far wide it went out for a throw-in on the left.

Chris Johnston then created an opportunity for himself at the other end, collecting the ball wide on the right then scampering infield, along the 18-yard line, to set up a shooting chance, but he could not keep the ball down. Robbie Muirhead, who had replaced Eremenko, then drew a fine one-handed save from Cierzniak with a powerful blast from 25 yards out. And that was that.