The Dutchman's side travel to Stamford Bridge on Boxing Day, and the 55-year-old is confident the Cottagers will give a much-improved performance against Chelsea
The Dutch coach told reporters on Friday: “I don't think we are lacking confidence, it's about teamwork.
“If you work as a team, we are good, and our goal difference has shown that.
“That's probably been a big plus for us this season, but that is something we destroyed on Wednesday with the five goals.
“If you concede early like we did, then you get tired as well and that's not what you want.
“In the second half we showed we wanted to play for ourselves, the team and the supporters. We could have got back into the game had it been 3-1 because we had chances, but it wasn't to be.”
The former Tottenham boss is keen for Fulham to bounce back in Boxing Day's west London derby against Chelsea at Stamford Bridge, and the 55-year-old believes his men will showcase their defensive abilities.
He added: “It's a good opportunity to show everyone that we can defend better.
“If we don't defend better we'll never win a game against a top side.
“It does not lift your confidence if you get a defeat like this, so you have to do a lot of talking for resolve.
“We've learned from this. We have to do better, be more aggressive, and if we have the ball, we must take the game to them.”
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