Arsenal boss Arsene Wenger has no plans for retirement yet

Arsenal manager Arsene Wenger knows he cannot go on in the job forever, but admits the thought of setting a retirement date is somewhat scary.

Manchester United boss Louis van Gaal has vowed to finally retire in 2017 at the end of his contract to uphold a long-standing promise to his wife.

It is a transition originally planned to have been made more than a decade ago by the 63-year-old Dutchman, who has delivered league titles at Barcelona and Bayern Munich as well as Ajax, where he also won the Champions League.

Earlier this week was the 19-year anniversary of Wenger's appointment at Highbury and he is now the longest-serving manager in the English game.

However, just how to f ollow the likes of Sir Alex Ferguson - who famously made a U-turn some 12 months on from his initial retirement announcement in May 2001 - is not on Wenger's immediate agenda.

"I haven't decided yet, I think it can be more instinctive and impulsive than that," said the Arsenal boss, whose contract runs until the summer of 2017.

"I am always scared - I have heard that so many times, 'next year I will retire' and then they continue or go somewhere else.

"I think one thing is for sure that, when I retire, I will really retire."

Arsenal head into Sunday's clash with United in the wake of a disappointing home defeat by Olympiacos in the Champions League on Tuesday night.

Wenger was left angered by the criticism of both his team selection, leaving Petr Cech on the bench as David Ospina's handling error led to a goal, and also the character of the players.

"What is boring is everybody says absolutely the same, that is for me boring. If it is the truth, you accept it. If it is not true, it is just cheap. That is boring," Wenger said.

"To kill a player like Ospina, he has been voted the best goalkeeper of the Copa America, he is on the Ballon D'Or list, he was by far the best goalkeeper of the Premier League in the second part of the season last year; I find that just sensationalism, it is not analysis of football.

"If it is combined with real analysis of numbers that justify that, I will say 'okay, they are right', but it is just because one guy on the television says something, everybody says exactly the same.

"I don't agree with that, it makes me angry because I think it is unfair to the player. This is a top, top quality player.

"Yes he made a big mistake, but that can happen to any player. It happened to Petr Cech, don't worry."

Arsenal's next European fixtures are a daunting double header against Group F leaders Bayern Munich.

Wenger, though, insists all is not lost.

"We are still in the Champions League, we are not out of the Champions League. Everybody writes us out, but we are not out," he said.

Wenger is confident Arsenal can produce the required response against United to lay down a marker for their own Barclays Premier League title challenge.

"We have a big game at home and the advantage is to win the big game at home," he said.

"It is the first maybe massive game for the top of the table.

"Without the home form, you don't win the championship, that is for sure."