Former Celtic midfielder Stiliyan Petrov has urged fans to give the club's new signings time to settle.

Petrov soon discovered the high demands placed on Celtic players when he arrived at Parkhead as a 19-year-old in 1999.

The Bulgarian was played out of position at wing-back as the Hoops toiled under John Barnes and his first manager lasted less than a year in Glasgow.

But Petrov established himself as a key player during the successful Martin O'Neill era before being reunited with the former Northern Ireland international at Aston Villa a year ago.

His replacement Gordon Strachan has brought in Scott Brown and Massimo Donati this summer to help fill the hole in midfield vacated by Petrov and Neil Lennon, while Scott McDonald and Chris Killen have bolstered Celtic's strikeforce.

The champions failed to hit the heights in their opening league clash on Sunday as they were held to a goalless draw by Kilmarnock at Celtic Park.

But Petrov, who keeps a close eye on his former club by watching their SPL games on Setanta, is sure they will improve.

He said: "I watched the last game against Kilmarnock. Unfortunately they couldn't get the result but it's a long season and they will show their strength.

"Gordon Strachan has brought in a lot of new players and they will need some time to gel.  That is normal for every club when they bring in so many new players but I think he will get it right.

"Celtic is a big team and some of the players came from small teams, but the manager has already told them what to do and what to expect.

"And from the pre-season games they are well aware of what to expect and what they need to show."

Brown draws immediate comparisons with Petrov, with both making their name as midfielders who aim to get beyond the strikers and score goals.

The 22-year-old has arrived in Glasgow with a weight of expectation following his £4.4million move from Hibernian as Celtic fans look for a goalscoring midfielder to replace Petrov.

But the Villa midfielder does not feel Brown should have to shoulder more pressure than anyone else.

The 28-year-old said: "It is not going to be about Scott Brown, it is going to be about the whole team - he needs to have some help from his team-mates.

"It is a club with high expectations and they expect a lot from all the players, not just from one.  He will show the fans he can do it, he will need to make his own name.

"He has always been tough opposition, he always gives his best in every game and that is what he is doing for Celtic now. He is somebody who plays with his heart and all the fans appreciate that, and he is doing that for them."  PA