Wenger insists that Almunia is sidelined due to fitness, not form

Manuel Almunia is injured and out of tonight's Champions League tie against Partizan Belgrade. How convenient. On Saturday Almunia, whom Arsène Wenger tried to replace with Mark Schwarzer during the summer, gave away a penalty and, though he saved it, was then at fault for two of the goals Arsenal conceded to West Bromwich Albion.

That sparked speculation that Almunia would be dropped, instead he is injured. But conspiracy theorists should not get too excited. Wenger's standby goalkeeper is not Shay Given, it is Lukasz Fabianski, last seen in Europe at Porto last season, committing two of his regular howlers.

Not, insisted Wenger, that he lacks faith in the Pole: "I have no concerns, only you [the media] do. He made the mistake in Porto but he can show he has learned from that."

Wenger, though, made it clear he would not have dropped Almunia and added: "The goalkeeper is always the easy scapegoat, but we win together and we lose together."

This is, nevertheless, a chance for Fabianski to claim the jersey, at least until the January transfer window opens. With hindsight Wenger may well have replaced Almunia at half-time on Saturday but the goalkeeper assured him the injury, incurred when giving away the penalty he subsequently saved, was not a handicap.

"We checked him at half-time," said Wenger yesterday, "he had some pain but said he could go on. So I decided to play him on. If a player says he is perfectly all right it is difficult to take him out, I would have done so if he said, 'I feel it'. Sometimes when you are playing and are hot, you do not feel it."

Almunia will not be the only change, and not just because Wenger is disappointed with Saturday's performance. He said the stats showed his players worked harder than in any game this season – probably because they were chasing the match – so a few need resting, especially with the weekend's encounter with Chelsea to consider.

"Some players need a breather. We have some fresh players as well." One of these is Jack Wilshere who was on the bench against West Brom. The Partizan Stadium can be an intimidating venue but then so is White Hart Lane for an Arsenal player and the teenager was unfazed by that. "I would not be afraid to play him," said Wenger. "I rested him for a breather, he is 18 and has played every single game recently."

The manager added: "The mood was very low because we were all disappointed. We had lot of possession but we made defensive mistakes. It was not a problem of leadership, or fitness. We did not get our priorities right. We need to defend first, be patient, and win the game when you can win it. We were in a rush to win the game and neglected our defensive duties. It is not a disaster. We have to have perspective. It is the first game we have lost this season. I will tell players to continue to play the way we want to play and to believe in themselves. The game we play needs a high level of confidence, so for us it is important confidence stays high."

Partizan have had some notable English scalps. They defeated Manchester United in the European Cup semi-final in 1966, losing to Real Madrid in the final, famously knocked QPR out of the 1984-85 Uefa Cup despite losing the first-leg 6-2 at Loftus Road, and beat Newcastle in a 2003 Champions League qualifier on penalties (prompting the line that the drinks were on Aaron Hughes, after he skied the decisive spot-kick, as he'd put £20m over the bar).

In recent years they have struggled in Europe, losing 10 of their last 11 Europa League and Champions League ties. The latest was a 1-0 loss at Shakhtar Donetsk in their opening Group H game, and Wenger expects them to try and hit Arsenal on the counter-attack.

Managed by the 36-year-old Aleksandar Stanojevic, Partizan may include Stefan Savic, a defender who had a trial with Arsenal last year, Bundesliga veteran Mladen Krstajic, and Medo, a 22-year-old from Sierra Leone who arrived in Belgrade via Finland, where he was granted asylum after his parents were killed in his home country's civil war.

Partizan have a long-standing reputation for crowd disorder and were thrown out of the Uefa Cup in 2007. That, however, was after violence marred a match against a Bosnian club, not so surprising given that the Balkan wars are still fresh in the memory. Although the RAF was involved in the coalition bombing of Belgrade there appears no overt anti-British hostility, but Arsenal have increased their own security while Partizan have appealed to their supporters to behave.