John Collins has backed Scott Brown to prove his critics wrong by showing he is worth every penny of the £4.4million Celtic paid for him.Brown was regarded as one of the brightest talents in the country when Celtic beat off competition from Rangers to land the midfielder in a record-breaking deal last summer.

However, the 22-year-old has so far failed to live up to that billing during his time in the east end of Glasgow, leading to discontent in some quarters regarding his contribution this season.

But Collins - the former Hibernian manager who sanctioned the move - insists Brown not only has the potential to inspire victory in Saturday's Old Firm derby, he also has all the makings of being a Celtic great one day.

"I have no doubts at all that Scott will turn into a top quality player for Celtic," he said.

"Remember, he is still a young player and this is his first year at a really big club and it's never easy in your first year.

"He is adapting to a new system, a new team, and different expectations.

"When you play for Celtic, you are under the spotlight every single week in front of full houses. That wasn't the case when he was at Hibs and he has to get used to that.

"But I've no doubt that he has the ability to win the game on Saturday for Celtic.

"People look at the £4.4million price tag and expect miracles but that isn't a huge amount of money in modern football.

"Trust me, £4.4million for Scott Brown was value for money."

Collins has also been watching the progress of another of his former players on the other side of the Old Firm divide and he believes Kevin Thomson is not fulfilling his potential at Rangers.

"He plays the sitting, holding role for Rangers and it's an unglamorous role," said Collins.

"He just takes the ball and plays simple passes and I think he's got more talent than that.

"I think he could do more and probably get further up the park and maybe get some strikes on target."

Both players are set to go head to head in Saturday's much-anticipated Old Firm derby which Collins believes Celtic cannot afford to lose as they attempt to bridge a three-point gap over a Rangers side with a game in hand.

"In the last few years Celtic have been out in front in the title race so the pressure is on now," he said.

"They are chasing Rangers and this is a game they can't afford to lose, it would be very difficult to come back from.

"They are two evenly-matched teams and there isn't much between between them but, to win at Ibrox, you have to play well."

Lack of funds was one of the reasons Collins walked away from Hibs earlier this season.

And, regardless of the outcome of the title race, he would like to see Gordon Strachan given cash to strengthen in the summer.

Rangers chairman Sir David Murray has already promised Walter Smith a healthy transfer kitty and Collins insists Strachan is just as deserving of money for new players.

He said: "Gordon hasn't spent a lot of money and he has won two back-to-back titles and has taken Celtic to the last 16 of the Champions League.

"I think now is the time for Celtic to give him a little bit more money in the summer but that's up to the Celtic board to decide, it's not my job."

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