Fletcher says that the experienced Dutch coach continuously tells the team to relax in training, and wants to ensure that a similar attitude is taken into matches over the coming weeks.
“The gaffer [Advocaat] always talks to us before training and tells us to relax, and not to let things get to us on the pitch," the striker said.
“It doesn’t get to us in training, and we have to make sure it doesn’t on a weekend either.
For Sunderland, relaxing in a competitive environment will be tough, as their need for points is so great due to their awful start.
Advocaat's side have just two points to their name so far this season, and there is growing unrest at the Stadium of Light.
With West Ham United the visitors to Wearside this weekend, there is a real need for the Black Cats to get their campaign up and running, and if they are unable to turn the corner, then the atmosphere is likely to turn sour.
Sunderland are currently in 18th place in the Premier League table, and are already four points adrift of safety.