BRISTOL City boss Steve Coppell will almost certainly be forced back into the transfer market in order to find a replacement for Sam Vokes.

Signed on loan from Premier League Wolves last week, the 20-year-old Wales international centre-forward was carried off just 13 minutes into his debut in Saturday's Championship opener against Millwall at Ashton Gate.

City's medical staff diagnosed a damaged hamstring and Vokes was sent for a hospital scan in Bristol yesterday afternoon.

Although Coppell is still awaiting the results, he fears the 6ft striker could be sidelined for a considerable time.

Already without the injured Nicky Maynard and Danny Haynes, last season's top goal-scorers, Coppell is once again perilously short of attacking options.

Coppell is actively scouring the market for a replacement for Vokes and hopes to make an addition to his squad before Saturday's return to Championship action at Doncaster Rovers.

"We're right on the edge as regards numbers and, to be honest we will have to look for another striker," said Coppell.

"Nicky Maynard is still a way away and we don't quite know what the Danny Haynes situation is. He's back doing some running and we hope he isn't too far away. But he's missed all of the pre-season and we're not sure how soon he will be back.

"It's a unique situation in my career and I've never known so many injuries."

He added: "Improving your squad is a byword for all managers and I've been looking to bring players in from my first day in the job.

"That was still the case even after I signed Sam Vokes, because he is just a loan. But strikers don't grow on trees and it's not as simple as just going out there and signing one."

Vokes' injury leaves David Clarkson as the only experienced forward available to Coppell for tonight's Carling Cup first round tie against Southend United at Roots Hall.

"Sam has had a scan and we are awaiting the outcome," said Coppell. "He was very sore when he came in this morning and we don't anticipate him being back next week.

"It looks as though the injury is significant and he could be out for some time.

"Sam is here until January under the terms of the loan and we'll do the best we can to look after him while he is injured. But he is a Wolves player and, if he is going to be out for a very long time, there is a possibility he may go back there during his rehabilitation."

Knocked out of the Carling Cup by League One Carlisle United a year ago, City will want to avoid a similar humiliation in Essex and Coppell is sure to warn his players against the dangers of complacency.

He said: "Southend will see us as a scalp and they'll be doing everything possible to knock out one of the big boys.

"They have financial problems and will see this as an opportunity to make some money. Of course, it's a potential banana skin and there are always shocks in the first round.

"We have to learn from what happened against Millwall, be stronger defensively, especially when dealing with set pieces, and go into the game with a winning mentality."

Coppell is keeping his starting line-up a closely guarded secret, but is expected to leave David James behind and give Dean Gerken a run out in goal.

Cole Skuse remains favourite to drop out of midfield and deputise for suspended centre-back Damion Stewart, who serves a one-match ban following his sending off on Saturday.