Liverpool wasted another chance to extend their lead at the top of the Premier League as a sub-par performance from Jurgen Klopp's men was punished in a 1-1 draw at West Ham on Monday.
Less than a week after missing the opportunity to go seven points clear of Manchester City with a 1-1 draw against Leicester, Liverpool's lead is now just three over the champions, who can now go top with victory at Everton on Wednesday.
Sadio Mane put the visitors in front at the London Stadium, but Michail Antonio quickly levelled and West Ham had the better chances to claim all three points when Declan Rice and Mark Noble failed to hit the target.
After posting a perfect record against opposition with the top six in their first 23 league games, Liverpool have now slipped up twice in as many matches to mount the tension in their chase for a first title in 29 years.
Klopp's side looked like a side playing under pressure in a lacklustre display as the absence of the injured Jordan Henderson, Georginio Wijnaldum and Trent Alexander-Arnold took its toll.
Hammers boss Manuel Pellegrini claimed it was "impossible to play worse" after his side's 3-0 capitulation to Wolves last week that followed a deeply disappointing FA Cup exit to League One AFC Wimbledon.
Even without the injured Marko Arnautovic, Pellegrini got the response he wanted in West Ham's performance if not their end product.
Javier Hernandez had the hosts' first chance but the Mexican and then Aaron Cresswell both fired inches wide of Alisson Becker's left-hand post.
James Milner was having a torrid time defending in an unfamiliar right-back role against the pace and trickery of Felipe Anderson.
However, the former England midfielder created the opening goal in controversial circumstances when given the chance to go forward.
Adam Lallana's neat footwork played in Milner, who was allowed to continue despite being clearly in an offside position, and Mane cleverly spun onto his cross to score his 12th goal of the season.
The lead lasted just six minutes as the visitors switched off from a well-worked free-kick and Antonio drilled Anderson's pass in off the far post.
More lax set-piece defending should have cost Liverpool again three minutes before the break when Rice headed wide another wicked Anderson free-kick delivery wide when completely unmarked 10 yards out.
Mohamed Salah was kept quiet for long spells, but the league's top scorer twice forced Lukasz Fabianski into action at the start of the second period.
On both occasions, though, the Egyptian lacked the power and accuracy to beat the Pole as he worked shooting opportunities onto his favoured left foot. Anderson continued to create problems at the other end and another positive break from the Brazilian should have created the winner when Noble fired over.
Divock Origi replaced the ineffective Roberto Firmino 15 minutes from time and the Belgian had a huge chance to make himself a hero as he did with a last gasp Merseyside derby winner against Everton in December.
This time, though, Origi shot meekly into Fabiankski's grateful arms with the final action of the match.