Ismaila Sarr's double and Troy Deeney's strike 18 minutes from time ended Liverpool's hopes of romping to a first league title in 30 years with an unbeaten season as they lost in the league for the first time since January 2019.

Jurgen Klopp's men still enjoy a 22-point lead at the top of the table, but their sluggish return from a two-week winter break earlier this month was finally punished.

After single-goal victories over struggling Norwich and West Ham either side of a Champions League defeat at Atletico Madrid, Liverpool were comprehensively beaten at Vicarage Road.

A 55-point gap separated the sides before kick-off, but the out-of-sorts visitors failed to muster even a single effort on goal in the first 45 minutes.

Gerard Deulofeu's dipping effort just did not come down in time as it landed on the roof of the net before he teed up Abdoulaye Doucoure, who saw his shot deflected behind by Virgil van Dijk.

Deulofeu then had to be stretchered off with a nasty looking knee injury that seems certain to end his season.

Watford's heads did not drop without one of their most dangerous players, though, as only Alisson Becker's fleetness of foot allowed the Brazilian international to save from Deeney deep into first-half stoppage time.

Andy Robertson's driven effort finally forced Ben Foster into a save early in the second half, but just as Liverpool were beginning to build up a head of steam, they were stung by two quick strikes by Sarr.

Firstly, the Senegalese beat Robertson to Doucoure's low cross to stab home at the near post.

Six minutes later, Sarr had too much pace for a flat-footed Liverpool defence as he raced onto Deeney's through ball and showed fantastic composure to lift the ball over the advancing Alisson.

Sarr also had a big part to play in Watford's third as he pounced on a short passback and had the vision to pick out Deeney, who lofted the ball nonchalantly over Alisson to make it 3-0.

Watford had thrown away a lead in three of their last four Premier League games to fall back into the bottom three.

But they never looked in any danger of doing so again as they moved back out of the relegation zone on goal difference.

Sarr should even have had a famous hat-trick with his final touch as he curled wide when one-on-one with Alisson.

However, that was the only gloss missing from a glorious night for Watford as Liverpool remain four wins away from the title.