Antonio Conte’s side are coming off the back of a shock defeat to Crystal Palace last weekend, whilst also enduring a tough mid-week draw with AS Roma in the Champions League.
Marco Silva’s men have been in a good turn of form recently, with The Hornets sitting above The Blues in the league table having picked up seven points in their last three matches, including a victory against Arsenal last weekend.
Chelsea have plenty of injury concerns ahead of their clash with Watford, with a couple more casualties added to the lengthy list already held in West London.
Goalscorer David Luiz had to come off in their thrilling draw with Roma on Wednesday night in the second-half after picking up a calf injury, although he did not look as though he was happy at being substituted off the field.
Tiemoue Bakayoko is another cause for concern for Conte, as the midfielder also picked up a groin injury during the group stage match, with both facing late fitness tests ahead of the early kick-off.
Danny Drinkwater continues to face time on the sidelines, not having made an appearance for The Blues since joining them from Leicester City on transfer deadline-day. He has a calf problem whilst former Foxes team-mate N’Golo Kanté is also missing.
The France international is nursing a hamstring problem he picked up whilst on international duty two weeks ago, whilst Victor Moses is also ruled out with the same problem.
Potential starting XI: Courtois; Cahill, Christensen, Rudiger; Bakayoko, Fabregas, Alonso, Zappacosta; Hazard, Pedro, Morata.
Silva’s side have been in top form in recent weeks, however, they will have their own problems when deciding their starting line-up for the match at Stamford Bridge.
Former Blues midfielder Nathaniel Chalobah is out of the game after he had to have an operation on his fractured knee cap, leaving him braced for a lengthy spell on the sidelines.
Craig Cathcart is also a long-term absentee for the Hornets, as he looks to recover from a knee injury that is expected to keep him out until 2018, along with Isaac Success.
Sebastian Prödl and Younes Kaboul are also unavailable for the Vicarage Road outfit, as the Austria international deals with a hamstring problem whilst the former Tottenham Hotspur defender copes with a knee problem.
Potential starting XI: Gomes; Mariappa, Kabasele, Britos; Femenia, Cleverley, Doucoure, Holebas; Pereyra, Richarlison, Gray.
The form book
Chelsea have a good record when it comes to their head-to-head record with Watford, having lost just once in their previous eight Premier League meetings, with that defeat coming in 1999.
Conte’s side have lost three Premier League matches already this season, leaving the Italian with a lot of work if they are to retain their title at the end of the year.
Silva has not lost an away game this season, taking 10 points from 12, and will be looking towards key man Richarlison to try and ensure that they can take at least a point from Chelsea back to the outskirts of London.