By Richard Clarke in Milan

Arsène Wenger believes in fairytales.

The Arsenal manager has witnessed a couple in the last six weeks of the season so you cannot blame him for having faith in the unfathomable.

Especially when Thierry Henry is the author.

The striker left Emirates Stadium in 2007 as a legend; the record goalscorer and perhaps the most charismatic player ever to pull on a red and white shirt.

He will depart the Club again after Wednesday's Champions League tie at Milan having assumed almost mythical status.

His loan spell from New York Red Bulls was justified in its first few minutes by that well-taken decider in a tight FA Cup Third-Round tie with Leeds United.

The utterly crucial 90th-minute winner at Sunderland on Saturday was a work of pure fiction.

The normally understated Wenger had billed this week as the biggest of the season - and the first game was the most important.

Henry's goal capped a late comeback which not only elevated his team to fourth in the Premier League but did something similar to the mood in the Arsenal camp ahead this mouthwatering last-16 tie.

The man with the new statue was helping to reconstruct his side’s season.

As usual in his second spell, Henry is highly likely to be a substitute on Wednesday. But, as usual, he presence will dominate.

The 34-year-old is well-known to the Italian crowd. He came to Arsenal from Serie A in 1999 and returned to haunt his old country four years later with two goals in a virtuoso performance against Inter at the San Siro stadium the two Milanese clubs share.

Win, lose or draw. Starter, substitute or 90-minute bench-warmer. It will be an emotional farewell for Henry. But it is interesting that Wenger, who sees this game as a classic 50:50, feels his former protégée is not only capable of creating the improbable on his own but he also has the capacity to haul the entire side to greater heights. Surely that makes Henry the 'go to guy' if, as expected, the game is still close in the latter stages.

"Thierry can do it again," said the manager firmly, "especially in a territory where he will be highly motivated. He started his international career in Italy so I believe that, if needed, he can help us.

"He has produced a lot of special moments because he’s a special player - just the number of goals he has scored shows that.

"But he also has a strength based on desire and belief. When he came on at Sunderland the other day there was suddenly a drive there and a focus to just do it. He comes on with that certainty and says ‘OK, let’s deliver'."

Surely a score draw or better would count as 'delivery' on Wednesday. Four years ago, late strikes by Cesc Fabregas and Emmanuel Adebayor at the San Siro proved pivotal after a goalless first leg at Emirates Stadium.

That was a Milan side overflowing with established stars who had won the tournament multiple times. It was a breakthrough victory for a young Arsenal outfit.

The current Milan have less winners medals in the competition but their names still roll off the tongue and Sunday's victory over Udinese sent them top of Serie A. Wenger feels victory would be another huge education for his new side.

"When we played here last time Milan had won the Champions League the year before and we knocked them out," he recalled. "We had a young, up-and-coming team that was full of confidence. When we arrived here I think we were top of the League.

"Since then we have lost some players of course but I feel we are again a strong team now. We are a team who is rebuilding confidence and I believe that Wednesday night’s game will be important for that process. Are we stronger or not [than that previous side]? I will give you the answer after the game."

Kieran Gibbs is expected to return at left back for the first time since October 16.

The loss of Per Mertesacker at Sunderland created the vacancy as Thomas Vermaelen will move to centre back. Wenger admitted he was loathe to change his defence and that Gibbs’s return was slightly ahead of time, but at least he now has a back four playing in their first-choice positions.

"Thomas has done extremely well as a full back," said Wenger. "When we played away from home recently with Sagna, Mertesacker, Koscielny and Vermaelen I felt the back four was very strong in the air.

"We didn't give chances away at Bolton, Sunderland and on set pieces we were comfortable.

"Offensively, we have got better and better in every game too. I was very happy and I would have kept it like that. But certainly Thomas is happy to be back in the centre!"

Much has been made of Milan's problems against English sides - they have been knocked out of the competition by Premier League opponents at this stage in their last three Champions League campaigns. In contrast Arsenal have won seven of the eight two-legged ties they have played against Italian sides. Wenger hardly sees a significance now we have reached the knockout stages.

“From this point on, it's a strange competition because it's a cup,” he said. “Anything can happen.

"In the past it has happened both ways [between English and Italian sides]. Milan knocked out Manchester United when they were very strong, before that, Inter came and beat us in London. But we’ve also won in Milan.

"There are different styles of play. The Italian style is more calculated, whereas English teams are less complex, often based on enthusiasm and rhythm. It really can go either way.

"Certainly this Milan side are the kind of team you can dominate and still lose, they showed that in Barcelona. We must also be cautious because they have individual players who can make a difference, like Ibrahimovic, Seedorf and Robinho.

"You fear Robinho more in the Champions League than the League as he can do something special on a big occasion.

"For me, this is a real 50:50," Wenger concluded. "Our attitude is very important in our first game. I believe they will start strong and it is important how much we win our fights in every area of the field.

"It will be the test of the season for us in the Champions League."

Team news

Arsenal: Mertesacker (ankle) Santos (ankle), Diaby (hamstring), Wilshere (ankle), Jenkinson (back).

Milan: Yepes (ankle), Aquilani (ankle), Merkel (knee) Nesta (thigh), Strasser (ankle) Gattuso (eye), Flamini (thigh), Cassano (heart surgery).

Match Facts

Tomas Rosicky is one booking away from a suspension in the Champions League.

Mathieu Flamini has not been named in Milan's 25-man squad for the Champions League. He hurt knee ligaments in a friendly against Juventus on August 21.

Renato Gattuso has not played since the first day of the season. The veteran midfielder has 'sixth nerve palsy', a dysfunction that affects eye movement.

Striker Antonio Cassano is out for the season having undergone heart surgery in November.

Milan lost their 13-month unbeaten record at home when Inter beat them 1-0 on January 15.

Copyright 2014 The Arsenal Football Club plc. Permission to use quotations from this article is granted subject to appropriate credit being given to www.arsenal.com as the source 15 Feb 2012