Ferguson announced his decision to leave Manchester United after 26 years on Wednesday, and lifted his 13th Premier League title after the 2-1 victory over Swansea City on Sunday.

But Wenger said there were signs throughout the season that the Scot would end his tenure.

"I was not surprised and I told my staff a long time ago that I thought it would be Alex Ferguson's last year," he said.

"So I was not completely surprised. I detected a few signs through the season, but there was already one of them before the season started that it could be his final year."

Arsenal host Wigan Athletic at the Emirates Stadium on Tuesday, as they look to claim a UEFA Champions League spot.

And the Frenchman is confident his side can continue their strong end-of-season run with victory over the FA Cup winners.

"It's a very important game for both sides, so you expect huge commitment from both teams," Wenger said.

"We're playing at home and we want to take advantage of our remarkable run. We have been hugely consistent and we are in a position where our destiny depends on us and we want to finish the job.

"Our destiny was not in our hands but we have done very well, so let's now finish the job, continue to play like we have and take the points."

The 63-year-old is anticipating a strong challenge against Wigan and paid praise to manager Roberto Martinez.

"Martinez has a positive philosophy, above all what you want is someone who tries to play good football and that's a good basis to move forward," he added.

"Both teams have to go for it, it's very difficult to know what will happen. It should be an open game, I think Wigan will be faithful to their shape which is based on solid defensive work and quick counter-attacking."

Wenger also revealed star midfielder Jack Wilshere will undergo minor surgery on his troublesome ankle in the next few days.

Wenger has attempted to allay any fears over the latest scheduled operation, though, saying the club expect him to recover in time to join his teammates for pre-season training.
"Jack will have small, mild surgery," the Frenchman told the club's official website. "It is a very small, small, small one. It is to remove a small pin. It will not be a problem.

"He will need very minor surgery, but we manage that as far as we can until the end of the season. At the moment, we use him only in games when I feel he is really needed.

"He won't be available for England in the forthcoming friendlies, but he will be back for pre-season. Of course he is disappointed to miss the England game in Brazil, but he will go next year (to the World Cup finals)."