But Gracia, making his first appearance at Vicarage Road since he signed a four-and-a-half year contract extension last week, said: "Nothing is impossible.

"You always have chances, and we want to take advantage of the chances we have.

"It will be difficult, and we know that, but playing at home with the support of our fans, I'm sure we will have some opportunities.

"Everybody knows it's difficult to get a good result against City, but they have drawn twice this season – maybe we are able to be the first getting a victory. You never know."

Watford have leaked 14 goals against City in their last three matches, while their last two fixtures at home to Guardiola's side have resulted in 5-0 and 6-0 thrashings.

The visitors, meanwhile, haven't lost on the road for 13 games but Gracia added: "I prefer not to focus on the stats and numbers because if we see the stats maybe we prefer not to play.

"I prefer to have the confidence in my players and their work. This way I'm sure we will have a good performance."

Watford could soon be boosted by the return of midfielder Tom Cleverley, who has been sidelined since January through injury.

Daryl Janmaat is also on the brink of a comeback following knee surgery which has kept him out for 10 weeks.

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