Watford 0-3 Liverpool: Mohamed Salah scores as 10-man Reds win at Vicarage Road

Trent Alexander-Arnold scored his first goal of the season for Liverpool with a stunning free-kick

Mohamed Salah set Liverpool on their way to a victory over Watford that kept them within two points of leaders Manchester City at the top of the Premier League.

Trent Alexander-Arnold's stunning free-kick and Roberto Firmino's tap-in added to the score for the Reds, but it was far from a comfortable afternoon for Jurgen Klopp's side, who had captain Jordan Henderson sent off in the second half.

Liverpool are now unbeaten in 13 league games in 2018-19 and have more points - 33 - than they have ever had at this point in a Premier League season before.

The five goals they have conceded is a defensive club record for this stage of a top-flight campaign, though they looked shaky at the back throughout on Saturday.

Hosts Watford were aggrieved not to be awarded a penalty when Reds defender Andy Robertson appeared to foul Will Hughes while the score was level.

It proved a pivotal moment for the Hornets, who were then unpicked by the visitors on the counter-attack once they had fallen behind to Salah's prodded effort from a move involving Firmino and Sadio Mane.

Though Liverpool were well short of their fluent best, the manner of this victory endorses their credentials as challengers to City.

Defeat meant Watford slip to ninth in the table.

• Relive the action from Vicarage Road

Flying full-backs make the difference

While Salah may have opened the scoring for Liverpool, Alexander-Arnold's second goal in the space of 10 days broke Watford's resistance in the second period.

It was a moment of undeniable quality from the right-back, who whipped a free-kick into the top corner from 25-yards after Adrian Mariappa had fouled Firmino.

He has now scored in consecutive matches after opening his account for England in the 3-0 win over the USA.

Up until that point, the visitors had looked unsettled by the perseverance of Javi Gracia's team, who forged several promising openings after capitalising on mistakes by the Reds.

However, Alexander-Arnold and left-back Robertson both came to the fore - though the latter was fortunate not to concede a penalty.

Both players enjoyed more touches than Liverpool's celebrated front three of Salah, Firmino and Sadio Mane, providing pace and purpose to the visitors' counter-attacking.

Not even Henderson's dismissal for two yellow cards - given for fouls on Isaac Success and Etienne Capoue - could stunt their attacking instincts.

And it was Robertson's galloping run down the left which ultimately laid on a late goal for Firmino, the Brazilian tapping in his fourth goal of the campaign after Mane had been denied by Watford goalkeeper Ben Foster.

Watford's Liverpool woe continues

Conceding possession and territory appeared to be part of Gracia's tactical plan from the start - and it worked initially as his team sat deep and frustrated Liverpool for long periods.

While the visitors enjoyed 69% of possession, it took almost 40 minutes for them to fashion a noteworthy opportunity.

In contrast, Gerard Deulofeu slammed a shot past the Liverpool goalkeeper Alisson inside two minutes after racing clear - but was correctly flagged offside.

Deulofeu then failed to collect a Tory Deeney through ball, before Alisson brilliantly turned away Roberto Pereyra's drive as the hosts sliced through the Liverpool defence.

But their wastefulness, and referee Jonathan Moss' decision not to penalise Robertson for a challenge on Hughes, ensured their dismal record against the Reds continued.

Despite going into Saturday's match with four victories from six home games this term, the Hornets have now failed to win 11 of their past 12 fixtures against Liverpool, losing 10.

Man of the match - Trent Alexander-Arnold (Liverpool)

Trent Alexander-Arnold scored his first club goal for almost 11 months - after opening his account for England during the international break

'It was closer than the scoreline' - what they said

Watford manager Javi Gracia, speaking to the Premier League: "The game was closer than the scoreline. We tried, we did a good defensive job for 66 minutes and after that the game changed. We had opportunities and didn't take them. Everyone knows Liverpool are a great team.

"I prefer not to speak about refereeing decisions. We accept something that is difficult to accept - but we do it and there is nothing else we can do.

"We could do better in the first half on the counter-attack but playing against Liverpool is always very demanding.

"I am optimistic, I can feel the ambition of the club and I feel happy training here."

Liverpool manager Jurgen Klopp told BBC Sport: "We stayed stubborn. They defended and counter-attacked and we had a few really good moments we didn't score, which is not a big problem if we stay on track.

"How we closed down the game was just brilliant, especially the third goal. The first goal was brilliant football and the free-kick from Trent [Alexander-Arnold] was a dream. It was a good game against a good side."

On Jordan Henderson's sending off: "It happens. Jordan Henderson was not happy about his mistake but what a guy he is. He has a heart like this, so sometimes it leads you on the wrong path. We wanted to change him but we were a little bit too late."

Watford stutter at home - the stats

• Watford have lost three of their past four home top-flight games (W1), as many defeats as they suffered in their previous 15 at Vicarage Road in the Premier League (W8 D4).

• Liverpool are unbeaten in their opening 13 matches of a Premier League season for the first time since 2007-08.

• Watford have lost 16 of their 18 Premier League matches against sides starting that day in the top two, beating Chelsea in September 1999 and Arsenal in January 2017.

• Liverpool's Mohamed Salah has six goals in his three league appearances against Watford.

• Salah has had a hand in six goals in his past five league matches for Liverpool (four goals, two assists) - as many as he managed in his previous 11.

• Liverpool defender Trent Alexander-Arnold has been directly involved in goals in consecutive Premier League appearances for the first time, assisting against Fulham before scoring against Watford.

• Liverpool's Roberto Firmino has been directly involved in eight goals in his past six league games against Watford (five goals, three assists).

What's next?

Watford travel to Leicester City next Saturday (15:00 GMT) for their next Premier League match. Liverpool visit Paris St-Germain on Wednesday in the Champions League (20:00 GMT) before hosting Everton in the Merseyside derby on Sunday 2 December (16:15 GMT)