Manchester City's Riyad Mahrez and Kyle Walker celebrate after the match. Photograph:( Reuters )
Bournemouth moved up with a 2-1 home win over lowly Huddersfield Town.
Manchester City were forced to defend deep in the final stages at Watford on Tuesday but ensured their title-chasing juggernaut kept rolling on with a 2-1 victory that extended their lead at the top of the Premier League to five points.
The defending champions, who are unbeaten in the league, were again without Argentine striker Sergio Aguero but close-season signing Riyad Mahrez showed his worth by setting up Leroy Sane for the first goal before scoring himself.
Bournemouth moved up to sixth with a 2-1 home win over lowly Huddersfield Town, while there were comfortable wins for West Ham United and 10-man Brighton & Hove Albion.
City were having trouble finding a way past Watford keeper Ben Foster at Vicarage Road but the Englishman will not want to see the replay of him being beaten by the chest of Sane five minutes before the break after a Mahrez cross.
Algerian Mahrez then fired home himself shortly after halftime to set Pep Guardiola's marauding side on the way to what looked like an easy victory.
Watford did not give up though and Abdoulaye Doucoure fired in from close range five minutes from time. The hosts, without a win since October, pushed City deep into their half but could not stop them claiming a 13th win in 15 league games this term.
Spectators have been accustomed to seeing City blowing teams away, particularly last season when they won the title with a record 100 points and scored a record number of goals.
It is not often that City resort to clearing the ball high and away from their defence as they did near the end at Watford, but Guardiola said the result was the most important thing.
"For five minutes they were better than us. It is not about breaking records, it's winning games. You cannot win easily for 38 games, that is impossible," the Spanish coach said.
The focus on Wednesday switches to second-placed Liverpool who visit Burnley looking to cut the gap back to two points.
Bournemouth's Callum Wilson and Ryan Fraser notched a goal and an assist each to snap the south-coast side's four-game losing streak with a 2-1 home win over Huddersfield Town.
Wilson gave the hosts the lead after five minutes with a superb header from a free kick that Fraser whipped in. Wilson returned the favour 17 minutes later by passing to the unmarked Fraser who slotted the ball past keeper Jonas Lossl.
Terence Kongolo pulled one back for the visitors seven minutes before halftime with a header butut it was not enough to stop Eddie Howe's side moving up to sixth spot.
Brighton were reduced to 10 men in the 'M23 derby' against Crystal Palace but still ran out comfortable 3-1 winners thanks to goals from Glenn Murray, Leon Balogun and Florin Andone.
Murray converted a 24th minute spot kick for his ninth goal of the season before Shane Duffy was sent off for a clash with Patrick van Aanholt after a penalty appeal was turned down.
The hosts doubled their lead just after the half-hour mark through substitute Balogun before Andone scored the third in first-half stoppage time.
Luka Milivojevic converted a late penalty for Palace after a foul on Wilfried Zaha but it was too late for Roy Hodgson's side who slipped to 15th, three points above the relegation zone.
Three is the magic number for West Ham with the 3-1 victory over Cardiff City at the London Stadium being their second successive win and they have scored three goals in each.
Lucas Perez came off the bench to score twice shortly after halftime before Michail Antonio headed home a third.
Cardiff's Josh Murphy bundled in a consolation but, with the bottom three playing on Wednesday, Neil Warnock's side could be in the drop zone by the time they host Southampton on Saturday.