An injury-ravaged Liverpool fought back from a goal down to beat Luton 4-1 and open up a four-point lead at the top of the Premier League on Wednesday.

Chiedozie Ogbene had given the Hatters a shock first-half lead against a Liverpool side missing Mohamed Salah, Darwin Nunez and Diogo Jota among others.

Dutch international duo Virgil van Dijk and Cody Gakpo turned the game on its head in two minutes just before the hour mark before Luis Diaz and Harvey Elliott secured the win.

Victory takes Jurgen Klopp's men four points clear of Manchester City and five ahead of third-placed Arsenal, but having played a game more than both their title rivals.

Liverpool's squad was already stretched by injuries prior to loss of Curtis Jones, Jota and Nunez in the first-half of Saturday's 4-1 win at Brentford.

Salah scored on his return from a hamstring injury at the weekend, but was forced on as a substitute earlier than planned and suffered a setback that kept him out.

Klopp was already without Alisson Becker, Trent Alexander-Arnold, Joel Matip and Thiago Alcantara due to injury and the stretched Reds were forced to work harder for the three points than they would have wished just days before the League Cup final.

Without the first-choice front three of Salah, Jota and Nunez, there was extra responsibility on Diaz but the Colombian had a first 45 minutes to forget.

Twice he had big chances to open the scoring in the first five minutes, but took too long to get his shot away and then fired wide.

Luton held Liverpool 1-1 when the sides met at Kenilworth Road in November and have made a habit of ruffling the feathers of the Premier League's elite on their return to the top flight.

However, the visitors had barely posed a threat before they went in front on 12 minutes.

Tahith Chong burst into the Liverpool box and when his powerful shot was parried by the legs of Caoimhin Kelleher, Ogbene headed in at the far post.

All of Liverpool's chances before the break continued to fall to Diaz. (AFP)