Manchester United manager Jose Mourinho has admitted that his side would be left in a "bad" position if they were to lose to Arsenal on Saturday.
United go into the match at Old Trafford trailing the Gunners by six points, while they are eight adrift of leaders Liverpool.
However, Mourinho is hopeful that the rivalry between United and Arsenal will inspire his players, playing down the historical element of his previous meetings with Gunners boss Arsene Wenger.
"I always think the end of December is a good moment to look and see where you are, to see the differences to the top and bottom of the league, to see the perspective for the second half of the season. We are in mid-November but we know Arsenal have six points more than us. We know the distance tomorrow can be three, six or nine and obviously nine would be bad, and three would be perfect," he told MUTV.
"Old Trafford will be full of emotion as always, so expectations are high for a big game. Every match is an isolated event – it has nothing to do with now. Mr Wenger was a different manager in 2004 to now; I was a different manager to now. The teams are completely different; he and I don't have one single player from that time – most of them are retired.
"So now it's just a big game between two of the best teams in the country. Rivalry is not just historical – it's about rivals for titles, and for a decade it was just between United and Arsenal. United were dominant but Arsenal had a period when they won titles, where they were unbeatable and so on.
"Everything was bigger in that period and it has kept on for the last 15 or 20 years. I think everybody likes that. The players are professional and know how to behave, so I don't think that's a problem. I think the rivalry can only affect the game in a positive way."
Mourinho's only defeat in 15 previous meetings with Wenger came in the 2015 Community Shield.