deeply about our selections and tactics and there may well be an element of playing safe.
"But don't count on it because it's a derby match when anything can happen and often does. The passion of the fans can easily spill over and affect the players so that tactics go out of the window as emotion takes over and each side, or both, slide into gung-ho mood. An early goal can dictate the shape of the same so, as I say, we could be in for a masterclass of attacking from both teams. In which case, hold onto your hats - and enjoy."
It already looks set to be a two-horse race for the league title with clear daylight between the two Manchester clubs and their nearest rivals; indeed, third and fourth-placed Chelsea and Tottenham currently lie 10 points behind leaders United. Nevertheless, Sir Alex says it's still too early to discount anyone in the race for the championship.
"At this time in the season you can't really say it's a two-horse race," he adds. "If you think back we were 12 points behind Chelsea at one point and when Arsenal beat us in the league in 1998 we were 11 points clear.
"The important thing for us is to take lessons from the mistakes we're making and do something about it. We need to find a solution."