The Blues headed into the game looking to get back to winning ways after the disappointment of their surprise defeat by Leicester City on Saturday.
Man of the match Hazard fired Chelsea FC into the lead in first-half stoppage time at Vicarage Road when he rounded Ben Foster and slotted home for his 100th goal for the Blues.
However, Watford were level at the break thanks to Roberto Pereyra’s equaliser.
But it was Hazard who ended up having the final say as he netted the eventual winner in the 58th minute from the penalty spot.
And former Chelsea FC star Nevin felt that Hazard was clearly the difference on Wednesday night.
Speaking during BBC Sport‘s coverage of the game, Nevin said: “In the end, the quality showed through.
“The quality was Eden Hazard above everybody else. some people do not like the idea of him playing up front, but he has won his team three points today.”
Meanwhile, Hazard himself opened up about his position up front during his post-match interview with Sky Sports.
Hazard said: “I can even play at centre back! My target is to score goals and to try and win the game, as a winger or a striker.
“I missed a couple of chances today, especially in the first half, but I scored two so its important to keep focus.
“We showed great character against Man City after defeat by Wolves, and today we did the same thing after a defeat by Leicester. When we fight together we are a top team.”
The win left Chelsea FC in fourth place in the Premier League table and 11 points behind leaders Liverpool FC.
The Blues are next in action when they take on Crystal Palace on Sunday afternoon.
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