Heidar Helguson is out of tomorrow's game with Middlesbrough after failing to recover from his calf injury in time and could even miss next Tuesday's clash with Ipswich Town.

Hornets boss Malky Mackay had hoped Helguson would be fit for this weekend's trip to the Riverside but we understand the striker suffered a minor setback this week in his recovery from the calf strain picked up during his second Watford 'debut' a month ago.

Mackay described the Iceland international's chances of making Tuesday's match as "touch and go" but conceded it was more likely he would make his return next Friday against Sheffield Wednesday.

"We don't want to rush him in for the sake of an extra two or three days and lose him for a couple of months," Mackay said.

"Our fitness department have worked very well and hard with him in terms of his rehab and the proper way he should recover from this calf strain and for the sake of Saturday and Tuesday ... it is probably looking more like Friday but I am not discounting Tuesday."

Mackay hinted he may receive some good news this weekend though, when captain Jay DeMerit visits an eye specialist tonight.

DeMerit has been out for a month after a bit of grit underneath his contact lens cut his right eye ball and it became infected.

There were fears the USA international, who has been in the States celebrating with the national squad this week following their qualification to the World Cup, would require surgery due to the scarring affecting his eye sight.

But Mackay said: "We will have some news on that in the next couple of days and there is a chance Jay might just be back a little bit quicker than we were hoping."

Beside DeMerit and Helguson, Watford have a fully-fit squad going into the game with third-placed Middlesbrough, who will include former Hornets loanee Adam Johnson and are managed by Watford-born Gareth Southgate.

One player who is expected to be involved is Nathan Ellington – who this week claimed it was "actually best" that he left Watford "pretty soon".

The Hornets are actively looking to reduce their wage bill and as one of the club's highest earners, Ellington was expected to leave in the summer.

The striker went on trial with Premier League side Blackburn Rovers at the beginning of this season but ended up staying at Vicarage Road, although the former Wigan Athletic man claims Rovers boss Sam Allardyce is still monitoring his situation.

Mackay has been full of praise for Ellington since pre-season and insists the 28-year-old's circumstances have not changed.

The Hornets boss said: "I don't think his situation has changed at all, it is just that he has done an interview on TV. I think in your interview with him last week he said the same and his situation hasn't changed since the start of the season.

"Financially the club has to be run in a certain way but until such times that an offer does come in for him or he goes somewhere, he is very much part of my squad as he has trained immaculately since day one of pre-season."

Another player whose Watford career could soon be over is left back Mat Sadler, who has not played for the club since Boxing Day last year.

Sadler, who joined from Birmingham City for £750,000 in January 2008, has been on trial at League One club Huddersfield Town this week and set up a goal in their Reserve side's 3-1 win on Tuesday.

Mackay said: "At the moment there are a couple of people ahead of him in his position and Mat is at an age where he wants to play football.

"He has gone up to Huddersfield and if they like what they see, there is a chance he will go out on loan but that is down to how he gets on up there and what Huddersfield think of him."