Watford boss Javi Gracia expects to face a vastly different Chelsea to the one his side dispatched last season.
The Blues arrived at Vicarage Road in February in Gracia's first home game in charge of Watford and found themselves on the end of a chastening 4-1 defeat.
That victory remains a fond memory for Gracia but the Spaniard knows it will have no bearing on the outcome when Maurizio Sarri's side come to town on Boxing Day.
"That was a good game. It was my first home game and it was special," said Gracia.
"But it's the past. Now is another game. It's different. We know it will be very demanding for us because we are playing against one of the best teams in the league.
"It's not easy because they have very good mechanism to attack. And they have very good players with different options.
"But to get a clean sheet at West Ham is something good for us. It shows us that working together with the solidarity we had, we can do well. We are able to compete and win."
Watford's 2-0 victory at the Hammers on Saturday moved them up to seventh and has Hornets fans dreaming of a potential European campaign next season.
But Gracia added: "When I saw the table after the game I saw the relegation zone starts at 12 points.
"I prefer to work day by day and try to enjoy the road, every moment. I like to compete against all the teams. We can compete with all of them.
"The next game will be the same. I prefer that than to be focused on positions in the table. Because we are in December and you know that football can change day by day."
Watford will have an unchanged squad as Will Hughes, Andre Gray, Sebastian Prodl and Adalberto Penaranda all remain sidelined.
