Arsenal will discover later on Monday morning whether captain Cesc Fabregas has won his fitness battle to face former club Barcelona in the Nou Camp.
The Gunners - already without Holland forward Robin van Persie and England winger Theo Walcott - are desperate for their talisman to take his place on the plane at Luton this afternoon.
Fabregas himself remains optimistic the hamstring problem, picked up in the Barclays Premier League clash against Stoke on February 23 and which ruled him out of the shock Carling Cup final defeat to Birmingham at Wembley, will have sufficiently healed to allow him to play some part against the club he left as a teenager.
Jack Wilshere used his Twitter account to allay fears he would be unavailable for the trip to Spain because of an ankle knock suffered in the frustrating goalless draw with Sunderland on Saturday. However, Gunners boss Arsene Wenger is not so confident midfield enforcer Alex Song will be able to shake off a knee injury to make the travelling squad.
"Alex Song has not been on the field at all," said the Arsenal manager. "We will make a test on Cesc on Monday."
Wenger accepts the trip to Barcelona has been weighing on the minds of his players, but fully expects them to raise their game in the Nou Camp.
Despite the disappointment of not being able to beat Sunderland in a game which Andrey Arshavin's second-half goal was incorrectly ruled offside, Arsenal did close the gap slightly on leaders Manchester United, who lost 3-1 at Liverpool yesterday afternoon.
Wenger concedes with such a massive European tie ahead of them it is perhaps understandable his team were not their usual fluid self against the Black Cats.
"Barcelona has been a little bit in the heads of the players, it is always subconscious," he said.
"However, now we have a big game on Tuesday and the size of the game will help. The team is mentally strong and the season is not over."
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