Diego Costa and Michy Batshuayi scored twice in the ultimate 10 minutes to secure a 2-1 victory over Watford and hold Antonio Conte's unbeaten start as Chelsea manager.
Batshuayi pounced seven minutes after being introduced at Vicarage road as Heurelho Gomes did not maintain an Eden Hazard shot, before Costa tucked dwelling the winner.
The Spain global raced clear with three minutes to play and coolly fired underneath Gomes to seal all three features, and lengthen Conte's undefeated run against Walter Mazzarri to seven league video games.
The Italian coaches fell out in 2011 after Conte was deemed to have copied Mazzarri's three-5-2 formation for a Juventus clash with Napoli, and they have continued a frosty relationship ever on the grounds that.
Etienne Capoue's 2d strike in as many games appeared to have ensured bragging rights for the Watford boss but Batshuayi and Costa had other suggestions.
Victory gives Conte two wins from two within the premier League, whilst Mazzarri is still ready for his first success within the Watford hotseat.
After early Chelsea stress, an unchanged Watford aspect settled into their rhythm on Mazzarri's home debut, and Jose Holebas brought the first retailer out of Thibaut Courtois after seven minutes.
Watford's attempts to maintain their optimistic have been almost undone moments later as Hazard created room for himself on the left and his low pass appeared destined for Costa at the again post just for Miguel Britos to make a central clearance.
The hosts have been preserving their possess, although, and midway through the 1/2 Nordin Amrabat bamboozled Cesar Azpilicueta on the right before offering a hazardous pass into the six-yard box that Odion Ighalo used to be unable to convert underneath strain from Gary Cahill.
With 1/2-time looming a raking cross-field cross from Branislav Ivanovic was fantastically introduced down by way of Nemanja Matic in the Watford penalty area. His cushioned volley noticed Costa slide in with Gomes, with the goalkeeper able to claim on the second try.
Ten minutes after the restart the sport had the purpose it had been lacking because the hosts struck through Capoue, the midfielder controlling an Adlene Guedioura cross on his chest before lashing past Courtois.
Falling behind for the first time this season fired Chelsea into existence and the viewers felt they should have been awarded a penalty 10 minutes later when a left-wing corner looked to be treated, however referee Jon Moss waved away their appeals.
Their pressure ultimately told, though, as Batshuayi - one in all three substitutes presented by means of Conte - made an instantaneous impact, the striker within the correct location on the right time to faucet residence from six yards.
And with time walking out Chelsea snatched all three elements, Costa released through alternative Cesc Fabregas to go away Conte dancing with joy on the sidelines.