Watford midfielder Damien Francis will be sidelined for six months after damaging cruciate knee ligaments.
Francis joins Gareth Williams and Moses Ashikodi on the sidelines
Francis was injured during Saturday's 1-1 draw with Manchester City, a result which relegated the Hornets.
Watford boss Aidy Boothroyd said: "I had been really pleased with Damien. He was starting to come into form, but his injury gives someone else a chance."
Watford have also lost Gareth Williams and Moses Ashikodi to serious injuries in recent weeks.
Midfielder Williams has a similar injury to Francis while striker Ashikodi has broken his leg.