Only a late u-turn kept him at Highbury and the disruption caused by that uncertainty, allied to two injury problems, affected his performances in the first half of the season.
However, firstly at Newcastle midweek and then at Charlton, Vieira proved he has returned to his best as he led Arsenal to vital wins.
Wenger declared: “Patrick was already good at Newcastle but was really dominant against Charlton. For a while, he hadn’t been completely right. But technically and physically, he is now as good as he can be.”
Wenger has already admitted that he believed Vieira was poised to move to Madrid before concluding that his bonds to Arsenal were simply too strong to break.
“He had spent eight years at the club and wondered for a while whether it was time for him to move or not. You have to accept that. It’s human,” insisted the Arsenal boss.
“He felt that his commitment to the club was questioned. But he is clear now. He was from the time that he decided to stay. It wasn’t accepted by everybody but I could understand that.
“There is a long and strong love story between Vieira and the Arsenal fans. When they felt that he might leave, of course they felt big pain. But the biggest worry for me was not his commitment, it was that he came back injured from the European Championships.
“He was out at the start of the season and then, when he came back again, everyone expected him straight away to be Patrick Vieira. It’s not magic like that.
“When he was back to his best against Aston Villa, he was injured again. That’s why he had maybe some slightly less good performances than we are used to.”
Wenger admitted that Vieira returned to action “too early” against Manchester United, which then affected his fitness in November. But having then also missed the key games against Rosenborg and Chelsea through suspension last month, Vieira is now at least back to his imperious best.
That is just as well, considering that Gilberto, Edu and Mathieu Flamini were all injured for the trip to The Valley. However, Arsenal came through that test, even though they were also without Dennis Bergkamp, Jose Antonio Reyes and Lauren.
A relatively inexperienced line-up were inspired also by Freddie Ljungberg, who scored twice as they recovered from conceding an equaliser on the stroke of half-time.
Teenager Cesc Fabregas, who partnered Vieira in midfield, and emerging striker Robin van Persie, who scored the third goal, also starred, while novice Justin Hoyte was assured at right-back.
Arsenal managed to maintain their five-point deficit to leaders Chelsea, although Wenger does not believe his side will have to remain unbeaten to overtake Jose Mourinho’s side.
“We don’t want to have another defeat, but I think Chelsea aren’t my worry at the moment. I go step by step - 40 points, then Europe, the Champions League and the championship,” Wenger stressed.