Mario Suarez could make his Watford debut against Chelsea tomorrow evening whilst Jose Holebas is fit to take the place of the ineligible Nathan Ake, who is on loan from the champions.

Holding midfielder Suarez completed his protracted move from Fiorentina on Saturday evening following the Hornets’ 1-0 FA Cup win at Nottingham Forest.

The three cap Spanish international has been training with the Quique Sanchez Flores’ side since and could make his debut when Guus Hiddink’s Blues visit Vicarage Road.

“Yes, he has trained with us for just three days but he’s fit,” said Flores on Tuesday morning.

“He doesn’t know at the moment how we play exactly but he knows me and I know this player.

“I think the adaptation time of top players is very quick.”

Watford will, though, be without the services of the impressive Ake who is on a season-long loan from Stamford Bridge.

The Netherlands Under-21 international cannot play against his parent club and it will therefore fall to Holebas to start at left-back.

Holebas’ last appearance came at Southampton last month and he played against the Blues on Boxing Day.

He has made just six Prenier League starts for the Hornets this season but seems the most likely candidate to step into the breach once more.

“He’s fit, he’s OK and training with a good mentality. I think he is ready,” confirmed Flores.

The Hornets picked up a creditable 2-2 draw at Chelsea in the first meeting between the two sides with Diego Costa netting twice in the game to kick-start a run of six goals in eight outings.

Costa worked under Flores at former club Atletico Madrid and the Watford boss has an unlikely admirer in the snarling Chelsea striker.

“I was talking with him (after the game at Stamford Bridge) and he told me: ‘I love your team, congratulations on coming here’,” said Flores.

“I said: ‘Diego, I see you’re quicker than before – two goals is too much.’ We were joking but I love Diego Costa because I trained him for one year and we have a good relationship.”

That game was Hiddink’s first of his second stint as interim manager and the veteran Dutch boss is unbeaten in eight games since returning.

Chelsea had lost seven of their previous 14 in all competitions before Hiddink replaced Jose Mourinho as manager. But Flores insists the west London outfit have always been a tough proposition.

He said: “I always think Chelsea are an amazing team. They have very good players, an amazing squad and a lot of possibilities to change players if they think something isn’t good during the match.

“It’s very difficult to play against Chelsea; they have amazing power in terms of the physical [aspect] but we played against this team a-month-and-half ago and we had the opportunity to win before finally we drew.

“Our expectation is very high; to win and to play well. Of course, we are really positive we can do something good.”

He continued: “We know they have the possibility to improve a lot because they’ve got Willian, Costa, (Eden) Hazard, Oscar, (Nemanja) Matic, (John Obi) Mikel and (Cesc) Fabregas.

"We know they have amazing players. Of course they have the possibility to achieve amazing targets.

“But our work at the moment is to be confident, try to make life very difficult for Chelsea on the pitch.

“We have our tools, our idea and our plan. In the first games against Manchester United, Tottenham, Hotspur Chelsea and Manchester City we were very close. I hope we have learned a lesson.”