Manchester United captain Nemanja, ahead of the match against Arsenal on Sunday, has said his team must continue to raise their performances.
After starting to bounce back after a slow start to the season, a loss at Old Trafford to Arsenal would be a huge blow to United's chances of defending their title.
Vidic said he has seen sign of an improving team, but that they need to continue to improve if they are to beat Arsenal.
"We have to step up for a big game like this. We have to prove to everyone, including our fans and ourselves, that we are good. That is the challenge for us," Vidic said.
"Arsenal have played really well this season but we have to show we can do better than we did in games like Manchester City.
"I have seen signs we are getting better but good players raise their performances in big games and Arsenal is definitely a big game and one we're looking forward to.
"This is different to recent years. We are looking at them more seriously. Arsenal are playing well, top of the league.
"They are in the best form of all the teams competing for the title and I think we need a performance at home.
"We need to pay attention to details and defend right, create chances and score goals.
"A lot of things are getting better and better, but we need them to be even better against Arsenal. They present challenges for defenders."