Paul Lambert is convinced new signing Stephen Pearson will become a big star at Celtic - but only in the long term.

Having lost Liam Miller to Manchester United, the Parkhead faithful will be expecting big things of the £350,000 signing.

But having been eased in as a late substitute in yesterday's Scottish Cup victory over Ross County, Pearson's new team-mate has warned the fans not to expect too much too soon.

"He will become a top player here," said Lambert. "I'm sure the good players around him will help him. He has showed what he can do and he is a very promising player.

"He is only young but give him time and I'm sure he will be a good addition to this club."

Pearson came on with 10 minutes remaining but an out-of-sorts Celtic had already scraped a 2-0 victory. Their reward for a far from convincing and controversial success was a tough away trip to Hearts.

Victory came following goals from John Hartson and Lambert.

Rangers manager Alex McLeish has told his players they need to turn nasty if they are to save their season.

McLeish is desperate for a winning run after a stuttering spell saw them crash out of Europe and fall further behind rivals Celtic in the league title race.

Last week's 3-0 defeat at Parkhead all but wrapped up the title for the unbeaten Hoops, who moved 11 points clear.

That left Rangers with only the defence of the two cups as realistic aims and they remain on course for that after disposing of Hibernian in the Scottish Cup.

Goals from Shota Arveladze and Peter Lovenkrands were enough to set up a fourth round clash at Kilmarnock next month.

Little quality football was played by either side in an often bad-tempered game that also saw Hibs midfielder Grant Brebner hospitalised with a dislocated shoulder and broken arm.

But following such an insipid derby performance McLeish was just glad to be back in the winners enclosure.

He said: "The players that Rangers employ have to be of a special breed and character. If the result last week destroys them then you know they are not right for the club.

"Arveladze was chasing back in the last five minutes and dispossessed a Hibs player in his own half. That's the type of work ethic all players should be inspired by.

"We all like to see the nice things in football but it is the ugly side that hasn't been 100 per cent for us this year."

SCOTTISH CUP: Fourth-round draw: Kilmarnock v Rangers; Hearts v Celtic; Spartans v Livingston; Motherwell v Queen of South; Clyde v Dunfermline; St Mirren v Inverness CT; Partick v Hamilton; Falkirk v Aberdeen or Dundee.

Ties to be played weekend of February 7th/8th.