He said: "We have a 12th man when we play European games at Parkhead and they can help us even up the score. It's so hard when you come to Barcelona and you're 30 seconds away from getting a great result. Everyone was gutted."
Celtic were on the brink of a famous draw in the Nou Camp until Jordi Alba stole in behind the defence to give the Spanish matadors a 2-1 win seconds from full-time.
An own goal from Javier Mascherano had given Celtic a first-half lead before Andres Iniesta pounced to level the scores just before half-time.
But the result means Neil Lennon's team remain second in Group G at the halfway stage and still have home games against Barca and Spartak Moscow to come.
And it left Wilson convinced that they have a real chance of making it to the last 16 – starting with a revenge match against Lionel Messi an Co in the return on November 7 at Parkhead.
"I would say that's the best defensive performance the team has produced in my time at Celtic," the central defender said.
"We've come here and although we've lost we'll take the positives from it, as well as the negatives, and I really think we'll be even better as a team because of this. The game plan was pretty simple, it was just 'when we don't have the ball: defend'.
"But that takes an enormous amount of hard work.
"It doesn't get harder than coming up against Lionel Messi in the Nou Camp, he's the best player in the world and maybe the best player ever."
Celtic could now defy the odds and finish ahead of second or third seeds Benfica or Spartak.
And Wilson insisted: "We're halfway through the group now and we've played everybody, we've seen what it's all about.
"I think we're all confident that we can get something out of this and hopefully move on to the next stage."