Tempers flare between Carlos Tevez and Rafael during the last derby
Manchester United face Manchester City at Old Trafford on Saturday after missing the chance to take a giant stride towards a 19th title - but with a swift opportunity to send an emphatic message to their rivals.
Sir Alex Ferguson's side will not have been nursing any sense of relief that their first Premier League defeat of the season at Wolves was not punished heavily as Arsenal lost a four-goal lead to draw at Newcastle United and Chelsea lost at home to Liverpool.
In my opinion, the title race would have been all over had United won at Molineux, but they slipped up and gave the chasing pack renewed hope that they can be caught. Had United claimed all three points, it would have meant they would have had to lose three more games while Arsenal won all of theirs, and realistically that was very unlikely to happen.
No-one should underestimate what a game of this magnitude means for both clubs. In assessing the current position, however, I believe it is a bigger game for Manchester United than Manchester City.
United have been presented with the sort of game, a local derby against close rivals both geographically and in the league table, to make a very significant statement.
The sign of the great team is how they respond to a setback. If United win they are right back in business and have demonstrated to the chasing pack that losing to Wolves was simply a blip. If they lose or draw, it is inevitable there will be some out there pointing to renewed frailty and saying the cracks are beginning to show. There may be some negatives vibes around, even some self-doubt.
Ferguson's team have got the title in their grasp. They can smell it. They have had an opportunity to really stretch away and missed it. You can be sure the manager will be reminding them that they will not come along very often.
I still think Manchester City lack the team ethos that is so vital in these crunch situations
Arsenal will have found no good news as they came off the pitch at Newcastle last Saturday, but their spirits will have been lifted by United's loss, and now it will be the aim of Ferguson and his players to show there are no signs of weakness.
We are reaching the real business end of the season and I notice some have even suggested Arsenal might be better losing in the Champions League to Barcelona so their load is lightened in pursuit of Manchester United. I dread to think what Joe Fagan and Bob Paisley would have said if someone in our Liverpool dressing room had suggested that - they may even have had to be forcibly restrained.
A winning mentality is a winning mentality and goes from game to game, competition to competition. Having lots of big games may be hard, but they are a lot easier when you are winning them.
Ferguson will be getting all the right messages over to his players this week, picked up and emphasised over the years of success and the result of all his vast experience of going the course and distance successfully in the Premier League.
It is not a result you would call with huge confidence. I would go with United with home advantage - but what an opportunity for City to do something to show they mean business and even revive their own hopes of winning the league.
The battle between Ferguson and Mancini will be eagerly anticipated
City have some very talented players, no-one can question that, but when it comes to winning titles I still think they lack the team ethos that is so vital in these crunch situations. Over the last six or eight weeks they have not looked like a team that was going to win the title.
They have huffed and puffed and I think if you are looking at a team other than United to win the league now it is Arsenal. This is the time to dig deep, not individually but collectively, and City have yet to prove they can do it.
Have they got the genuine alliances and spirit within the team structure to dig deep? Have they got the leaders who will lead by example? Have they got the guys who will bale you out when you are really in trouble? I'm not sure those questions have been answered satisfactorily.
At Liverpool, every time we went down the tunnel it was about sticking together. It was the message given to everyone, especially in the last 20 minutes before kick-off. Yes, we had great individual players but the staff always emphasised to us that if anyone tried to do it individually we would fall down. This mantra is even more important in the last eight or ten games of a season.
The key figures at Old Trafford are obvious ones. Wayne Rooney's contribution will be crucial for Manchester United as will Carlos Tevez's for City, while I would also throw Joe Hart into that equation.
Manchester City's England goalkeeper has not had the best of times recently. He is only a kid and it will be a massive atmosphere so this will be a real test for him.
It will be a test for everyone - but if United can recover from that reverse at Molineux and win I believe it will put them right back on course to claim the Premier League title.
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