The Blues make the trip to Vicarage Road to take on Walter Mazzarri’s Hornets just five days after the west London side opened their Premier League campaign with a home clash against West Ham.
Diego Costa’s late winner sealed a 2-1 victory over Slaven Bilic’s side after Wales defender James Collins had earlier cancelled out Eden Hazard’s second-half penalty.
Watford, meanwhile, drew 1-1 with Southampton at St Mary’s last weekend as Mazzarri started his reign as Hornets manager with a credible draw.
Former Arsenal and England midfielder Merson believes Chelsea will secure another three points against Watford at Vicarage Road on Saturday.
“I thought Chelsea played well against West Ham. They got lucky, don’t get me wrong, because Diego Costa should have gone but it was a good start against a solid team,” Merson told Sky Sports.
“Watford were outstanding against Southampton in the first half at St Mary’s and their defensive shape worked a treat. They had the Saints penned back at times, which was impressive.
“There are positive signs for Walter Mazzarri, but I’m going for Chelsea to edge it at Vicarage Road.”
Antonio Conte was appointed as Guus Hiddink’s permanent successor earlier this year after Chelsea’s disappointing defence of their Premier League crown last term.
The west London side are in third place in the Premier League table behind leaders Manchester United and Liverpool.
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