Watford will be without midfielders John Eustace and Stephen McGinn against Millwall.
Captain Eustace will sit out a one-match suspension after he was sent-off during the closing stages of last weekend's 1-1 draw at Doncaster, while McGinn is beginning a lengthy lay-off.
McGinn suffered a serious knee ligament injury in the 37th minute at the Keepmoat Stadium and will miss the rest of the campaign.
To make matters worse for Hornets boss Malky Mackay, his replacement Danny Drinkwater suffered a thigh injury in the same match and returned to parent club Manchester United for treatment this week.
He is rated as touch and go for Saturday but winger Will Buckley has recovered from his ankle injury and can play.
Full-back Lloyd Doyley remains sidelined with a hamstring injury.
Lions boss Kenny Jackett could hand new signing Martin Rowlands his debut when he takes his team to Vicarage Road.
The on-loan QPR midfielder was an unused substitute during the goalless draw with promotion hopefuls Nottingham Forest last weekend but could be thrown into the starting line-up to face the Hornets following a full week of training with his new team-mates.
January signing Josh McQuoid is likely return to the squad for the first time in over a month following an ankle injury.
The former Bournemouth striker played for the reserves on Tuesday prompting Jackett to tell the News Shopper: "Josh McQuoid is 100% after the reserve game on Tuesday and I would expect him to be a substitute at Watford."
Midfielder Jimmy Abdou is out until at least mid-April with a knee problem, while defender Jack Smith and striker Shaun Batt are also sidelined.