|Sol Campbell could make his first European appearance since 2006 [GALLO/GETTY]
Andrey Arshavin was one of five first team regulars left out of the Arsenal team as they flew out to Portugal for their Champions league last 16 first leg clash against two-time European champions Porto.
Russia winger Arshavin has been sidelined with a hamstring injury, joining striker Eduardo and goalkeeper Manuel Almunia as Arsenal's injury situation worsens.
Meanwhile midfielder Alex Song (knee) and defender William Gallas (back) have also been ruled out by the English Premier League club.
Manager Arsene Wenger was already resigned to being without Arshavin and Song for the knockout round, first-leg match but the loss of Gallas, Eduardo and goalkeeper Almunia further limits his options.
Long-term absentees Robin van Persie, Kieran Gibbs and Johan Djourou are also absent but striker Carlos Vela returns from a knee injury.
Former Gunners captain Sol Campbell, now in his second spell with the London club, could make his first European appearance for Arsenal on Wednesday since he scored in their 2006 Champions League final defeat by Barcelona in Paris.
The Gunners have had a drama-filled domestic season so far, lacking consistency in the league and exiting the FA Cup and League Cup.
The Champions League could be their best chance of ending a five-year title drought.
Recent defeats against rivals Manchester United and Chelsea raised questions about Arsenal's title credentials, with the team looking particularly vulnerable against counter-attacks and set pieces.
A win over Liverpool lifted Arsenal to third in the domestic league and restored confidence, but Arsenal will meet a club boasting an impressive European pedigree with Porto.
Porto are into the last 16 for the sixth time in seven seasons. Last season, Porto beat Arsenal 2-0 in Portugal in the group phase.
"This game is wide open. It could go either way,'' Porto coach Jesualdo Ferreira said.
"This match is an important test of our true quality"
"This match is an important test of our true quality. We really want to reach the quarterfinals, and this is one of the most difficult opponents we could have come up against.''
The Gunners were beaten finalists in the 2006 final and last season reached the semi-finals, only to be beaten by Manchester United.
Porto are still in the running for four trophies. As well as the Champions League, the team are unbeaten at home to sit third in the league, and have reached the latter stages of two Portuguese cup competitions.
The addition during the January transfer window of playmaker Ruben Micael has brought a marked improvement in Porto's fluency, though Micael is an injury doubt for the match.
Midfielder Cristian Rodriguez is also in doubt but Portugal's Raul Meireles should return and Ferreira has only Colombian Radamel Falcao available as a centre forward.
"FC Porto has a strong record and a certain stature in this competition,'' defender Bruno Alves said.
"Arsenal is well organised and has world class players. They're strong in every part of the pitch, though (Cesc) Fabregas is obviously a class player and crucial in their attacking build-up.