Arsène Wenger is prepared to sacrifice the chance to win Champions League Group B in order to improve the club's worrying domestic form.

With Arsenal in 10th place after the 2-0 home defeat by Swansea City on Saturday, the worst start to a Premier League season since Wenger became manager in 1996, he will not take a full-strength squad to Greece for tomorrow's match against Olympiakos, which Arsenal must win if they are to have a chance to finish as group leaders and – in theory – secure an easier draw in the first knockout round.

With a place in the top three the only guarantee of entry into next season's competition, his priority is to rest players he thought looked tired against Swansea ahead of next weekend's home Premier League game with West Bromwich Albion, when another poor home performance would certainly mean a repeat of the boos that greeted the final whistle on Saturday – as well as further damaging the team's league prospects.

Even before the two late goals that won the match for Swansea there had been a feeling of unrest in the ground. The Black Scarf Movement of disaffected fans held a pre-match protest against the board's financial direction, but Wenger refused to blame the present situation on club policies that have forced the sale of star players such as Robin van Persie and Cesc Fabregas.

"It's too early to say that," Wenger said. "We lost a game that we of course didn't want to lose, that is for sure. I can't deny that the quality was not there. It's difficult to come into deep analysis on the basis of the game. At home we have struggled with confidence and belief. But today was a more physical factor than psychological."

Wenger insisted that he is not influenced by the fans' reactions. "No – I focus on my job, honestly. I want our fans to be happy and to be over the moon, but I cannot say it affects the way I feel. Because I feel I have to focus on the job to see how we can sort our problems out."

That may involve signings in January, when he believes that funds will be available, but more urgent work awaits. "You know, until January we have a lot of important games, so we will decide that in January. But at the moment we have to find solutions before January."

He also remains confident that he is the best man to find the answers and steer the club back towards the top four. "Yes, of course," he said. "If you ask me always about my future, I can only give you one answer. I always respected my contracts, and that is it."