Swansea's recent decline and return to the Premier League dropzone is a surprise to Watford boss Walter Mazzarri, the head coach has said.
The Swans had looked to be on the up since the arrival of Paul Clement earlier this season, but have picked up only a point from their last five games and have fallen two points adrift of safety with six games remaining.
Mazzarri is emploring his players not to take the south Wales club too lightly, however, given they have already turned over Liverpool and others since Clement took charge.
He said: "Every game is difficult, and every game is important. Swansea won against Liverpool and has beaten Leicester and Crystal Palace.
"This can only show how hard it will be tomorrow, but that doesn’t mean we don’t think we won’t give our best tomorrow.
"I’m surprised they have dropped back. They have a good squad and team, I don’t know what really happened but even from the beginning of the year but they have players like Fernando Llorente who can make a difference.
"We will need to be together tomorrow and we will need the support of the fans."