Chelsea boss Andre Villas-Boas has dismissed the significance of mind games ahead of the club's clash with Sir Alex Ferguson's side.
The Manchester United manager has become known as a mind-game expert in his time at Old Trafford, following feuds with rival managers Kevin Keegan, Arsene Wenger and Rafa Benitez.
However, the former Porto boss is adamant that what is most important is a team's belief in their manager.
"Regarding the mind games, I really don't know how to position myself," he said. "I will wait and see if I need to respond or not, but it's the players who are most important.
"You can react in different ways, and tell players different things. The most important thing is for the players to have belief in the manager. If they don't, they might think the manager is subjective to pressure.
"Last year, at Porto, I had my disagreements with the Benfica boss, which was normal when they were threatening for the title. But it had no effect on the title race."
The Blues are two points beneath the defending champions, but can leapfrog United with a win at Old Trafford this weekend.
