Robin van Persie will always be "an Arsenal man" to Arsene Wenger.
The Gunners head to Manchester United on Sunday looking to consolidate their place at the top of the Barclays Premier League and on the back of an impressive 1-0 Champions League win away in Dortmund.
Former Arsenal captain Van Persie left the Emirates Stadium in August 2012 when he was sold reluctantly by the club to United for £24million, going on to score 26 goals as Sir Alex Ferguson's men delivered the title.
This season it is the Holland international's former club who are setting the pace, moving five points clear after beating Liverpool last weekend, with United down in eighth place.
Wenger admits it still does not sit well to see the player he signed as a 20-year-old in 2004 wearing the red of United rather than Arsenal.
"Of course it's strange because for me he is an Arsenal man," said Gunners manager Wenger.
"I took him when he was a very, very young player. We have gone together through very difficult periods and he became a world-class player and for me he is an Arsenal player."
Wenger, though, revealed the presence of Dutch coach Rene Meulensteen on the United staff also influenced Van Persie's decision.
"Robin van Persie had been convinced by the Dutch coach who was at Manchester United, (so) that played a big part," Wenger said.
"It was more the fact that I had the conversations I had with Robin van Persie that convinced me, it is not the talk with Alex Ferguson that convinced me to sell Robin van Persie to Man United.
"It is the head-to-head talks I had with Van Persie many, many times that convinced me that I had to sell him."
Wenger refused to be drawn on whether Van Persie, who was desperate to win silverware, might now regret his decision to leave as Arsenal look set for an overdue sustained title challenge.
"Only Robin van Persie can tell you that. I'm not in the position to do that," Wenger said.
"I think in the end I had to decide, 'Do I do it or not?' knowing I will get huge criticism for doing it.
"But I just decided because at the end of the day I felt it was the best thing to do."
Wenger also feels it will be "a bit strange" to take on a United side at Old Trafford without Ferguson in the opposing dugout.
New Red Devils boss David Moyes endured a tough start to his new job, but the side are coming together on the back of an unbeaten eight-match run in all competitions since losing at home to West Brom.
Wenger said: "David Moyes has shown great competence at Everton, so you need to leave him time to really get a grip on Man United, and he is slowly doing that. You see it now in the results.
"When someone has been there for 26 years and goes, it takes time for the guy who comes in.
"It is very dangerous and difficult for the manager who comes in.
"For me, Moyes is dealing very well with the situation."
Arsenal have won eight of their opening 10 Premier League games, and another victory at Old Trafford would see them open up an 11-point lead over the Red Devils.
Wenger said: "We have confidence, but what is at stake is consistency at the top level for us and to be capable of repeating the performances in our last two games, that will certainly be very important for the future of our team."
Arsenal will check on the fitness of England midfielder Jack Wilshere, who has been troubled by an inflamed ankle, while Mathieu Flamini should feature again following his groin problem.