London - Liverpool's 44-game unbeaten run in the Premier League was ended in spectacular style by a 3-0 defeat at Watford on another weekend when those hoping to join the Reds in the Champions League next season stumbled.

Leicester lost at bottom-of-the-table Norwich, Chelsea were held at Bournemouth, Manchester United drew 1-1 at Everton and Tottenham twice surrendered a lead to lose 3-2 to Wolves.

Here are three things we learned from the Premier League weekend:

Liverpool lose invincibility

The European champions should still cruise to a first league title in 30 years with a 22-point lead at the top of the table, but one extra element to a historic season has now eluded them.

Liverpool had dropped just two points in their previous 36 league games, but were beaten in comprehensive fashion at Vicarage Road as Ismaila Sarr struck twice and teed up Troy Deeney to seal a famous win for the Hornets.

Jurgen Klopp's men have failed to match their own extremely high standards since returning from a two-week winter break earlier this month.

After a run of conceding one goal in 11 league games, they have conceded five in a week to struggling West Ham and Watford.

Klopp now has the task of ensuring a spectacular season is not over when the title is clinched in the coming weeks.

A trip to Chelsea in the FA Cup fifth round awaits on Tuesday, while Liverpool must overturn a 1-0 first leg deficit when they host Atletico Madrid second leg of their Champions League last 16 tie on March 11.

Competitive if not classic season

Watford's victory was also another one for the competitive balance of the Premier League.

Third-placed Leicester have taken just one point from two meetings with Norwich as have Chelsea in their two clashes against Bournemouth.

The bottom six are separated by just seven points, while the struggles of the traditional top six outside of Liverpool and Manchester City's two-season European ban means Sheffield United, Wolves and Burnley have a realistic shot at the Champions League.

Poor results in Europe over the past two weeks for Premier League clubs have confirmed the suspicion that this is far from a classic season in terms of quality.

But that drop off from the cream of the crop and the capability of the sides at the other end of the table to cause a surprise has fostered an unpredictability not seen in the Premier League for a number of years.

"The surprise to me is that Watford are fighting to stay in the league," said Klopp.

Wolves feast on leaky Spurs

Attempting to rally the troops after a chastening week, Tottenham boss Jose Mourinho had urged his players to fight to "survive" in the Champions League race until their injury-hit squad is back to full power.

But Mourinho's words fell on deaf ears as his team crumbled in the face of Wolves' fearless display in their 3-2 win at the Tottenham Hotspur Stadium on Sunday.

Although Tottenham were without the injured Harry Kane, Son Heung-min, Moussa Sissoko and Hugo Lloris, it was their defensive deficiencies that proved fatal.

Dropping Toby Alderweireld and Jan Vertonghen did little to improve a creaky back five that was brutally exposed by Wolves.

Despite leading 1-0 and 2-1, Tottenham were never comfortable and second-half goals from Diogo Jota and Raul Jimenez lifted Wolves above their hosts into six place.

Amazingly, it is the first time in Mourinho's managerial career that he has lost a league game at home having led at half-time.