Celtic 4 Dundee United 0:Two goals from Gary Hooper helped Celtic to a convincing home win over Dundee United and undoubtedly stiffened manager Neil Lennon's resolve to get the best price possible for the striker if he is to leave Parkhead this month.

Before kick-off Lennon confirmed that his striker had turned down a contract offer while also revealing that the club had turned down another offer from Norwich after rejecting a bid, reported to be about £5 million, for the 24-year-old last week.

Hooper, who has 18 months left on his current deal, showed why he is attracting increasing interest when he converted a Georgios Samaras pass in the 19th minute before midfielder Victor Wanyama headed in number two before the break.

Former Scunthorpe striker Hooper struck again 10 minutes from time to take his tally to 22 before he set up substitute Scott Brown for the fourth as United, whose boss Peter Houston will leave at the end of the season, were left thankful that their defeat had not been more demoralising.

Lennon tinkered with his side following their 4-1 home win over Hearts at the weekend, in which Hooper had also grabbed a double.

Defender Thomas Rogne, midfielder Beram Kayal and striker Lassad Nouioui came in for Adam Matthews, Brown and Kris Commons, the latter out of the squad altogether with a rib injury.

United were unchanged from their fine 3-2 win against Kilmarnock at Rugby Park on Saturday with Jon Daly leading the line supported by Johnny Russell, who grabbed a hat-trick against the Ayrshire side.

Celtic were captained by Samaras and in the third minute he headed a Charlie Mulgrew free-kick past the post from eight yards. However, a minute later United Gary Mackay-Steven missed a great chance to open the scoring after a one-two with Russell left him through against Lukasz Zaluska.

With the Hoops defence missing, the United winger had time and space but his shot slipped past the far post.

In an unusually open start to the game, Hooper hooked the ball wide of the target before former Celtic midfielder Willo Flood fired off target from the edge of the box.

As the home side took another turn to attack, Hooper headed a Samaras cross over the bar from six yards and the match continued to swing from end to end with both defences looking porous.

It was Celtic who were first to benefit when Lassad raced away on a counter-attack with the United rearguard chasing, and when he moved the ball wide to Samaras his first-time pass to the unmarked Hooper saw him confidently beating United keeper Radoslaw Cierzniak.

In the 32nd minute Celtic should have doubled their lead when Hooper sent Lassad clear but a great tackle by defender Gavin Gunning thwarted the striker at the expense of a corner. However the loss of the second goal was only delayed.

Mulgrew’s corner was cleared out to Mikael Lustig and when he swung a cross to the back post the unmarked Wanyama powered a header back across goal and into the net.

Three minutes from the break Wanyama headed a Mulgrew corner off the post before United managed to keep the ball out for the concession of another corner, which was taken short by Mulgrew to Samaras who drove just wide of the far post.

Celtic started the second half with Lassad heading Joe Ledley’s cross over from six yards and there was little to suggest United could stage a comeback.

Daly’s powerful downward header from a Barry Douglas corner on the hour mark was blocked in a packed penalty area and followed by a weak Russell header which was comfortable saved by Zaluska.

Celtic remained in control and dangerous on the break.

In the 69th minute Samaras got on the end of Emilio Izaguirre’s cross from the left but Cierzniak saved before the visitors survived another spell of activity around their box.

Samaras then escaped the United defence down the left but his cross was well cleared by Douglas a yard from goal for yet another corner, which came to nothing.

However, 10 minutes from time Celtic broke with pace again and Samaras set up Hooper to score with a neat flick at the near post.

Anthony Stokes replaced Lassad to make his first appearance since last August after recovering from an ankle injury, but it was Brown, on for Kayal, who curled in goal number four after taking a Hooper pass, to leave the champions 12 points clear of Inverness at the top of the table.

However, the focus over the next few days at least, will remain on Hooper.