NICKY Southall will get the chance to make his mark in the Premiership in the heat of tonight's derby duel with Blackburn.

The midfielder, signed on a Bosman free transfer from Gillingham in the closed season, stands in for the injured Per Frandsen in the Ewood Park encounter Sam Allardyce acknowledges as the first major test of Wanderers' character since they won promotion back to the top flight in May.

It will be a first Premiership start for the 29-year-old Middlesbrough-born player, who has played all his football in the lower divisions - spending his formative years at Hartlepool then impressing with Grimsby before his four seasons as the Gills' playmaker.

But he steps up from a "shadow" squad Allardyce and his coaches are determined to keep on a constant state of alert.

"They have to be ready for their chances when they come along," the manager explained, "because they might only get the one chance.

"If they are not ready to take it, that will be the end of it. The responsibility lies with them to stay on top of their fitness and and be ready for the chance when it comes along."

Southall, who has had three runouts as substitute in the league plus a full game against Walsall in the Worthington Cup last week, comes into a midfield stretched by injuries. Frandsen, whom he replaced in Saturday's home defeat by Southampton, has joined Gareth Farrelly and Djibril Diawara on the casualty list and is expected to be out for at least a fortnight with ankle ligament damage.

Wanderers are likely to be otherwise unchanged as they look to bounce back from their first setback since their Play-off triumph in Cardiff against an injury-hit Rovers, who have made a stuttering start to their Premiershiup campaign.

Paul Warhurst is the only one of four former Blackburn players who will make the starting line-up - Frandsen injured while the best Colin Hendry and Leam Richardson can hope for are places on the subs' bench. New signings Bruno Ngotty and Rod Wallace have been told they must work on their fitness before they are ready to join the squad.

Allardyce, who saw his side well beaten by Rovers in the last two of their series of four league and FA Cup encounters last season, says the way they react to the Southampton defeat will be a measure of their Premiership credentials. "The response after a defeat is always crucial," he says, "no matter what time of the season or what position you are in."

Wanderers have sold their allocation of tickets for Saturday's game at Arsenal and are urging supporters without tickets not to travel to the game.