Arsenal (1) v Chelsea (1) Highbury, 7.45 It is up to Arsenal to show that minds can heal as speedily as bodies. On Saturday afternoon, following their FA Cup semi-final defeat to Manchester United, the diagnosis had Jose Antonio Reyes out for three weeks with medial ligament damage and Freddie Ljungberg sidelined with a broken hand.

Now they both have a chance of appearing in tonight's return leg of the Champions League semi-final against Chelsea.

Arsene Wenger could start to minister instead to the morale of a side denied its chance of a third successive FA Cup by United. There was a hint from Claudio Ranieri, his opposite number at Chelsea, that it could send Arsenal into a tailspin that will alter the season.

"It would be a bad moment for them," the Italian said with a meaningful look.

Wenger has to encourage the belief in his squad that a sequence of 17 games against Chelsea without defeat will be extended tonight. With a 1-1 draw from the first leg at Stamford Bridge, his situation appears favourable.

In practice, though, the Arsenal manager has to stifle the fears he was voicing before his hopes of a treble were ended.

"You never know what the psychological consequences of a defeat will be on your team," he had said.

It was time yesterday to adopt a different tone.

"You read the prognosis in the newspapers at the beginning of the season - we were nowhere. We are already beyond expectation and we can just make it greater than it is at the moment. We are very good physically, there is no problem.

"When you lose a game it is never coincidence, but I feel the games in front of us are so big that we do not want to spoil it because we are disappointed by Saturday's result.

"At some stage of the season, people will say that (you are on the slide), but we're unbeaten in the past six Champions League and 30 Premiership games.

"We have every reason to believe we are strong because of the history of the team. We have a great self-belief and team spirit, so we will get over that disappointment."

The long-held superiority of Wenger's side is useful camouflage for Ranieri.

"If they win it is nothing," he said, "but if we win anything could happen."

The Italian would not accept that his side are so lowly as to be underdogs. "I want to be the owner, not the dog," he said.

Chelsea are four league points behind Arsenal having played a match more, and success tonight could push the Highbury side into a decline that reopens the contest for the title. Having kept a clean sheet and won every away Champions League fixture this season, the visitors' effectiveness is not in question.

Ranieri's hope, though, does not rest on a belief that Arsenal will simply totter and crash.

"Against Manchester United they didn't want to fight 100 per cent," he said. "If they had wanted to get to the (FA Cup) final Wenger would have played with all his players, with Thierry Henry on from the start."

The Arsenal manager would not agree, but it is merely an ankle problem which niggles at Reyes, and Ljungberg, with the help of an injection, will be available.

Wenger also moved to insist that his side are not feeling the strain of their fixture schedule.

"We have the statistics that show we are still very good physically," he said. "We analyse the physical performances of the players, how much they run or sprint during games. So you know when your players start to dive or go down a little bit - at least in performance!"

The game could hinge on the tactics of the managers. Wenger has proved himself a master with subtle changes that have often swung games. If needs dictate, he will not hesitate to go for broke.

Ranieri loves to change and has earned the nickname "Tinkerman", but he is committed to attacking football.

Surprisingly, he tried to settle for a draw at Highbury early in the season at 1-1, but was undone by an error from goalkeeper Carlo Cudicini and has never repeated such negativity.

Ranieri used to catch the tube to watch Wenger's side. Last night Chelsea were staying at a hotel before making the short journey. This time Ranieri is coming to Highbury in earnest and his team will not pause to admire the opposition.

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