Watford have been dealt a significant blow with the news that Younes Kaboul could be sidelined for the remainder of the season.
The experienced centre-back had to be replaced by Daryl Janmaat after 42 minutes in their 1-0 win over Sunderland at Vicarage Road on Saturday after injuring his hamstring.
He faces an assessment at the club before a final prognosis can be made, but any involvement in the midweek clash with West Brom has been scratched.
And Hornets boss Walter Mazzarri told the club's official website how much of a blow it will be to lose the 31-year-old.
He said: "He's a very important player. It doesn't look good – he won't be available for Tuesday.
"We haven't been very lucky with injuries this season and because of this, we should have more points than we do."
Up next for Watford is a midweek clash with West Brom and despite beating Sunderland last time out, Mazzarri feels his side should be working to convert more of their chances.
He explained: "We had a really good game against Sunderland and I was very, very happy.
"We must improve on the last pass and we need to improve our finishing. We could have closed the game before we did."