Manchester United manager Sir Alex Ferguson bemoaned the failure of referee Chris Foy to give his side a penalty as they slipped to a 1-0 defeat at Arsenal.
Although Ferguson admitted Arsenal had a good case for their own penalty when Vidic handled in the first half, he felt hard done by.
"It's too big a game not to get the decisions right,'' Ferguson told Sky Sports News. "It balances out in that respect but I think it was difficult to see that one (Vidic's handball) but the one at the end, Clichy knew, he put his hands up in horror.
"Obviously, it gives Chelsea a major chance now and that's what happens when you get these decisions. They got one at Old Trafford last season so that's the worry now. But in terms of ability - a game at Old Trafford, the supporters will be ready for it - and so will our players.''
The Scot conceded his team had disappointed until Arsenal scored through Aaron Ramsey in the 56th minute.
"After that we dominated and I think we deserved something,'' he said. "I think we didn't use the ball properly but once we lost the goal we were in their half most of the time.
"We have a big week ahead,'' said the United boss. "Wednesday is a European semi-final second leg and then the game on Sunday, so two massive games. We will regroup and freshen it up.
"I will make some changes on Wednesday without question. I will bring Paul Scholes back in, Dimitar Berbatov, Michael Owen. We'll need to do that but I will probably keep my experienced players at the back.''
Should United lose next week, they will surrender top spot, on the slimmest of goal differences, with two games remaining and turn the title race into a two-game shoot-out
"We are in as good a position as you could ever wish for at the start of the season - semi-final of the European Cup, second leg, two-goal lead and go into a home game on Sunday level on goal difference.''
Arsenal manager Arsene Wenger said it would have been easy for Foy to miss Vidic's handball.
He said: "It was handball, yes. I really think the referee did not see it, but what can you do about it? I don't know.. You can give a penalty [to United] as well. I saw it on television, but I feel it is less obvious than the Vidic one by far.''
"We had a good performance, with everything in it - discipline, fighting spirit and our usual passing game. Until we scored the goal, I feel we controlled the game completely, then because we had not won a lot recently we tried to protect our advantage and were a bit under pressure.
"If you look at the age of the team, I think it is a big encouragement for the club because we had a very young midfield and were still very positive in our play.''
"We have gone through a difficult period. The team maybe lacks a bit of maturity under pressure, the team also had to deal with some big disappointments, and I felt that had a subconscious effect on our team.
"For me, it was immense pressure to be out of the title race, believe me, because I felt so strongly we would win this championship. I have not given up any hope, because we want to fight until the last second of the season.
"We were really unlucky this season until now, let's hope we have a bit more luck in the final three weeks - you never know.''
Wenger believes Arsenal's title challenge evaporated in the space of a week after they failed to beat Liverpool when leading with a stoppage-time penalty, then could not hold onto a 3-1 lead at Tottenham before a 16-match unbeaten run came to an end with a last-minute defeat at Bolton.
"We could have made nine points in these games, and plus the win today, we would have been ahead of Manchester United,'' he said. "We want to add what is needed, but I am very cautious with what I say because it can be turned both ways.
"It is very important for the club that we keep faith in what we do - you can see that the players grow when they get a chance, like Wojciech Szczesny compared to two months ago, he has grown. It is a law in our game, you can only grow at some stage if you play. People want both.
"They want to win every game and they want to produce as well fantastic quality young players. But if [Jack] Wilshere has grown this season, it is because he has played. However, on the other hand, if you do not win, the same people say 'why do you play young players?'''
Midfielder Samir Nasri was replaced at half-time with "a small hamstring problem'', with Wenger hopeful both he and Fabregas will be fit for next Sunday's trip to Stoke.
Robin van Persie claimed his side "wanted it more''.
And Van Persie said of the Vidic incident: "A clear penalty and in my opinion a straight red.''
Asked what the referee had said to him, he replied: "At first nothing because he wasn't sure, but I asked him again just after half-time and he said it wasn't a penalty but I'm sure if he sees it again then he will agree with me.
"If that [United's penalty appeal wrongly turned down] is the case then it's 1-1 on that one but in the end I think we played better today. We wanted it more. They played just on the counter-attack so in the end I think a fair result.
"It was all about pride today. The fans were great. It was up to us to show some dignity and some honour. We did that today so we're very pleased with that.''
Match-winner Ramsey - only in the team because of a thigh injury to captain Cesc Fabregas - urged Arsenal to press on and finish the season on a high.
"Our target was just to keep going now until the end of the season, to win all our games and see where we end up from there,'' he said. "We've done the first bit today. We've still got a few more games left so hopefully we can win them as well.''