Match ends, Watford 1, Chelsea 2.
Goalkeeper Ben Foster was denied a stunning headed equaliser in stoppage time as Chelsea hung on for victory at Watford to move third in the Premier League.
In blustery conditions, the visitors opened the scoring after five minutes when Jorginho's delicious pass allowed Tammy Abraham to lift in his 10th goal of the season.
Foster made two superb stops to prevent Frank Lampard's side going further ahead before the break as he denied both Christian Pulisic and Mason Mount.
But he could not prevent Pulisic following up his hat-trick against Burnley last Saturday with another goal as the American tucked in Abraham's low cross.
Watford, who remain bottom of the Premier League and are still searching for their first league win of the season, were handed a lifeline when Gerard Deulofeu tucked in a video assistant referee-awarded penalty, his first goal of the season.
And the hosts almost equalised when Foster's header deep in injury time was superbly saved by Chelsea goalkeeper Kepa Arrizabalaga, who sparked celebrations among his team-mates with the last action of the match.
But overall, Watford could not match a superior Chelsea side who recorded a fifth successive away win in the league, and a club-record equalling seventh away victory in all competitions.
Lampard's side can slip back into fourth behind Leicester, who face Crystal Palace on Sunday and have a superior goal difference, yet it was another impressive step forward for his young side who are now two points behind second-place Manchester City.
Chelsea show style and substance in gritty win
Chelsea's defeat by Manchester United in the Carabao Cup ended their seven-game winning run, but on the evidence of this game it has done little to dent their confidence.
With Abraham, Mount and Willian restored to the team, and Jorginho and Mateo Kovacic pulling the strings in midfield, Watford struggled to get hold of the ball in the early stages.
When the hosts finally had a sustained period of possession after half an hour, they could have been three goals down.
Abraham's opener was a work of wonder from Jorginho, who is now a fans' favourite after becoming a lightning rod for the frustration last season under Maurizio Sarri.
But Chelsea's top scorer could have had a second as Foster also stopped Pulisic's header and somehow tipped Mount's shot onto the bar, also denying the midfielder again in the second half after a fast break.
Although Chelsea finished third last season, their away form often faltered under Sarri. This season, however, they are showing steel, suggesting that a similar finish may be possible despite losing Eden Hazard in the summer and being in the midst of a two-window transfer ban.
Win eludes Watford again despite soft penalty
Watford boss Quique Sanchez Flores said in his programme notes that he can "feel" his team getting closer to their first Premier League win of the season following three successive draws.
Setting up in 5-3-2 system, they had to contain Chelsea for the first half hour, as the visitors threatened to put the game out of sight.
But following Foster's heroics, they grew into the game as half-time approached, giving their shivering fans something to warm to.
Deulofeu's fizzing effort was the closest they came before the break and Kurt Zouma had to be sharp to block Andre Gray's early second-half shot.
Once Pulisic scored his fourth of the season, the game looked to have petered out and yet there was still time for VAR to intervene with 10 minutes remaining.
Having been on the wrong end of two VAR decisions against Tottenham last month, Watford will not have minded that the penalty award looked soft.
Jorginho appeared to trip Deulofeu but the contact looked minimal, with referee Anthony Taylor deciding against the spot-kick.
The VAR thought differently, and although Watford pressed for an equaliser with Arrizabalaga saving from Foster's header in injury time, Chelsea fans were able serenade "Super Frankie Lampard" once again on the road.
Man of the match - Jorginho (Chelsea)
'If I score at the end that's me retiring' - reaction
Watford goalkeeper Ben Foster, speaking to Match of the Day: "If I score at the end that's me retiring. Fair play to Kepa - that was some save.
"Chelsea are a very good team with a lot of good energetic players, it is good for them and for England. But we can hold our head up high for hanging on until the end. We could have nicked something."
Watford manager Quique Sanchez Flores: "In the last minute Kepa had to do an amazing save, we're fighting against very good teams but our idea of football remains the same.
"The match was very tough but we had an opportunity to draw it. When we are positive on the pitch we are a good team and we can compete very well.
"I trust the players we have, some are coming back from injuries and others are tired, but right now it is about experience and managing our next challenges.
"We have positives, we are able to do good things but this does not happen for a full match.
"It's tough for the players but we need to go for the positive moments and make them more."
Hornets get the Blues again - stats
- Chelsea have won seven consecutive away games in all competitions - their joint-longest winning run on the road in the club's history (also seven between February-April 1989 under former boss Bobby Campbell).
- Watford have failed to win any of their opening 11 games to a league season for the first time in their history (D5 L6). They are the first team to do so in the Premier League since QPR in 2012-13.
- Chelsea have won consecutive away games against Watford for the very first time in the top-flight of English football, having also won this exact fixture last season (1-2).
- Abraham has scored seven goals in his six away appearances in the league this season - only Kevin Phillips in 1999-00 (Sunderland) and Manchester City duo Edin Dzeko in 2011-12 and Sergio Aguero in 2016-17 (all eight) have scored more in their opening six away games of a Premier League season.
- Pulisic has been directly involved in nine goals for Chelsea in all competitions this season (four goals, five assists); only Abraham has been involved in more (12) - while eight of those nine goal involvements have come away from Stamford Bridge, including all four goals.
- Jorginho has been directly involved in three goals in his 11 Premier League games this season (one goal, two assists), already more than he managed in his 37 such appearances last season (two goals, no assists).
- Deulofeu has scored his first goal from his 26th shot in the Premier League this season - his shot conversion rate of 3.8% is the joint-lowest of players to score in the competition in 2019-20 (along with Arsenal's Nicolas Pepe, also 1/26).
Chelsea host Ajax in the Champions League on Tuesday (20:00 GMT) and are back at Stamford Bridge on Saturday (12:30) for their match against Crystal Palace. The Hornets are at Norwich next Friday (20:00).
- 2JanmaatBooked at 70minsSubstituted forFemeníaat 75'minutes
- 27KabaseleBooked at 46mins
- 4DawsonBooked at 82mins
- 15CathcartSubstituted forMariappaat 20'minutesBooked at 88mins
- 14ChalobahSubstituted forHughesat 67'minutes
- 5JorginhoBooked at 89mins
- 10WillianSubstituted forJamesat 90+5'minutes
- 19MountBooked at 90mins
- 22PulisicSubstituted forHudson-Odoiat 83'minutes
- 9AbrahamSubstituted forBatshuayiat 88'minutes
- Anthony Taylor
- Shots on Target
Second Half ends, Watford 1, Chelsea 2.
Corner, Watford. Conceded by Kepa Arrizabalaga.
Attempt saved. Ben Foster (Watford) header from the centre of the box is saved in the bottom right corner. Assisted by Abdoulaye Doucouré with a headed pass.
Mason Mount (Chelsea) is shown the yellow card.
Foul by Mason Mount (Chelsea).
Abdoulaye Doucouré (Watford) wins a free kick in the attacking half.
Attempt missed. Adam Masina (Watford) header from the centre of the box misses to the left. Assisted by Kiko Femenía.
Substitution, Chelsea. Reece James replaces Willian because of an injury.
Attempt blocked. Abdoulaye Doucouré (Watford) left footed shot from outside the box is blocked. Assisted by Will Hughes.
Attempt blocked. Michy Batshuayi (Chelsea) left footed shot from the left side of the box is blocked. Assisted by Emerson.
Jorginho (Chelsea) is shown the yellow card.
Adrian Mariappa (Watford) is shown the yellow card for a bad foul.
Michy Batshuayi (Chelsea) wins a free kick on the right wing.
Foul by Adrian Mariappa (Watford).
Substitution, Chelsea. Michy Batshuayi replaces Tammy Abraham.
Foul by Jorginho (Chelsea).
Gerard Deulofeu (Watford) wins a free kick in the defensive half.
Attempt blocked. Tammy Abraham (Chelsea) right footed shot from the centre of the box is blocked. Assisted by Willian with a cross.
Willian (Chelsea) wins a free kick in the defensive half.