Naby Keita taken to hospital after complaining of back pain during Liverpool's defeat to Napoli

The injury leaves the midfielder's chances of featuring against Manchester City on Sunday in serious doubt

Liverpool face an anxious wait to determine the fitness of Naby Keita after the midfielder was taken to hospital with a back injury sustained during Wednesday’s 1-0 defeat to Napoli.

Keita was taken off on a stretcher after just 19 minutes of the Champions League clash in Naples after complaining of severe back pain, to be replaced by club captain Jordan Henderson.

Liverpool have not yet ruled the Guinea international out of Sunday’s match against Premier League champions Manchester City, but the issue throws his participation into significant doubt.

“I heard it's a back problem, but we don't know exactly - we have to wait,” Jurgen Klopp said after the game, which was settled in Napoli’s favour by Lorenzo Insigne’s 90th-minute goal.

Naby Keita receives medical treatment (Getty)

A statement published on Liverpool’s official website added: “Keita was transferred to a local hospital with the club doctor, where – with the midfielder's agreement – he underwent a number of precautionary health checks to assess his condition.”

Liverpool also said that “no decision has yet been taken” on when Keita will be discharged from hospital, though he is expected to travel back with the rest of the squad to Merseyside.

The result at San Paolo sent Napoli to the top of Group C on four points, one ahead of Liverpool and Paris Saint-Germain, who thrashed Red Star Belgrade 6-1 in the French capital.

Liverpool agreed to sign Keita in a £48 million deal from RB Leipzig in the summer of 2017 but the midfielder did not move to Anfield until 12 months later. He has made nine appearances for the club in all competitions this season.