Diogo Jota came off the bench to score the winner five minutes from time as Liverpool came from behind to beat West Ham 2-1 and move three points clear at the top of the Premier League on Saturday.
Pablo Fornals took advantage of a depleted Liverpool defence to put the visitors in front early on, but just as against Sheffield United last weekend, Jurgen Klopp's men fought back thanks to Jota's flying start to his Liverpool career.
Despite scoring against the Blades and Midtjylland in the Champions League in midweek, the Portuguese had to settle for a place on the bench.
But after Mohamed Salah levelled from the penalty spot, Jota scored twice in quick succession after being introduced 20 minutes from time.
Jota's first effort was ruled out after a VAR review for a foul by Sadio Mane, but as they so often showed by scoring late winners in their romp to the title last season, Liverpool were not to be denied as the Portuguese fired home from Xherdan Shaqiri's pass.
Liverpool's defensive woes without the injured Virgil van Dijk continued as they have now conceded more goals than any other side in the Premier League this season.
Nathaniel Phillips made his league debut for the champions at the heart of the defence with Joel Matip and Fabinho also out injured.
But it was Liverpool's other first-choice centre-back Joe Gomez who was at fault for the opening goal as his misplaced header went straight to Fornals, whose low shot found the bottom corner via the inside of the post.
David Moyes's men had been on an impressive unbeaten run in the Premier League, taking eight points from games against Wolves, Leicester, Tottenham and Manchester City over the past month.
The visitors sat in doggedly to defend their lead, but lacked threat on the counter-attack to add to it without the injured Michail Antonio.
And the Hammers gave Liverpool a route back into the game three minutes before half-time when Salah made the most of Arthur Masuaku's challenge to win a penalty.
The Egyptian smashed home his 14th consecutive successful spot-kick to bring the Reds level and ward off a potential first league defeat at Anfield since April 2017.
Masuaku nearly made amends early in the second-half putting in a low cross for Fornals who could only shoot tamely into the arms of Alisson Becker.
However, the vast majority of the action was still taking place in the West Ham half as Liverpool penned the visitors back.
Klopp turned to Jota and Shaqiri for inspiration off the bench and the changes worked to perfection.
Jota thought he had scored the winner earlier as he smashed home a loose ball after Mane clashed with Lukasz Fabianski and Angelo Ogbonna, but the goal was ruled out for a foul by the Senegalese.
But the Portuguese did register his fourth goal in seven Liverpool appearances since joining from Wolves in September as he kept his head with a cool finish from Shaqiri's brilliant pass to open up the mass ranks of West Ham defence.