Liverpool have confirmed Glen Johnson suffered a medial ligament injury to his right knee during Tuesday night's match at Aston Villa.
The England right-back was assessed by the club's medical team at Melwood and underwent a scan which revealed the extent of the injury which forced him to limp off after 88 minutes of the 1-0 victory at Villa Park.
A club spokesman said: "A scan has revealed a tear in the medial ligament in Glen's right knee. The player will see a specialist tomorrow (Thursday), after which we should be able to more accurately determine the length of his rehabilitation period."
Fans of both Liverpool and England will be hoping Johnson is not facing a long spell on the sidelines.
The 25-year-old left Villa Park on crutches - as a precaution - and has already missed three games this season with calf and groin problems.
It is the latest setback in a season that has seen influential pair Steven Gerrard and Fernando Torres struggle to overcome injuries, while £20million midfielder Alberto Aquilani's debut was delayed by ankle trouble.
However, Jamie Carragher believes Liverpool's victory against Villa was a statement of intent to their rivals that they are still a major force in the battle for a Champions League spot.
He said: "Over the last few years Villa have been one of those teams around the top six alongside Everton.
"But this time around Manchester City have really come on and Tottenham have done really well and I think they are all looking at us as the team they can take the place of.
"So it was more than just the three points at Villa. It was a statement to everyone that we are still fighting for that place."
Copyright (c) PA Sport 2009, All Rights Reserved.
Do YOU want to write for GiveMeSport? Get started today by signing-up and submitting an article HERE: http://gms.to/writeforgms