Liverpool romped to a convincing 5-0 win over Watford at Vicarage Road with Roberto Firmino netting a hat-trick as the Hornets produced a hapless showing in Claudio Ranieri's first game in charge.

Sadio Mane opened the scoring with his 100th Premier League goal, calmly finishing first-time into the bottom corner from Mohamed Salah's lovely ball in behind.

Firmino profited from poor Watford defending to find the net either side of half-time, tapping in from James Milner's pass after the home defence had been carved open, before pouncing on a loose ball from a badly defended cross.

Salah then scored a sensational solo goal, making a mockery of three defenders' attempts to win the ball from him before curling emphatically into the far corner, while Firmino struck again in stoppage-time to compound the hosts' misery.