Liverpool not optimistic over Naby Keita injury - sources

Orphans to receive over 100 Mane Liverpool shirts (0:35)

KitAid and Friends of Mulanje Orphans have teamed up to distribute Sadio Mane shirts to underprivileged children in Malawi. (0:35)

Naby Keita's hamstring injury is of concern to Liverpool ahead of Saturday's trip to Huddersfield Town, a source has told ESPN FC, but Mohamed Salah, Sadio Mane and Virgil van Dijk are yet to be ruled out after having issues over the international break.

Keita was forced off in Guinea's Africa Cup of Nations qualifier in Rwanda on Tuesday, which was played on an artificial surface at the Stade Regional Nyamirambo. He returned to Liverpool on Wednesday and underwent a scan on his left hamstring.

The nature of the issue means there is less optimism about Keita's condition in comparison to the other players who handed Jurgen Klopp injury scares over the international break.

Salah was taken off in the late stages of Egypt's game with Swaziland last Friday with a suspected groin injury. Although the national side's assistant coach Hany Ramzy did not consider it to be serious, Salah withdrew from Javier Aguirre's squad as a result, which then spared him a journey of over 6000 kilometres to Swaziland for the return fixture.

There were claims in Egypt, before Salah's groin complaint, that Liverpool had requested to the Egyptian Football Association (EFA) that Salah miss at least one of the Swaziland encounters for fear of stress and fatigue.

A spokesperson for the EFA said the "allegations are incorrect", but did confirm Salah arrived at the Egypt squad with a report on his medical condition -- as is common practice.

Liverpool have not yet ruled Mane out of the Huddersfield game, despite breaking a bone in his hand. The forward could play with a protective cast on his left hand, should the club be willing to take the risk.

Mane underwent an operation on Wednesday on his fractured thumb, sustained during Senegal's win over Sudan on Saturday.

Vian Dijk, meanwhile, has been battling broken ribs for several weeks, according to Netherlands boss Ronald Koeman.

However, the defender has only missed one game for Liverpool this season and since his rib injury came to light -- a Carabao Cup third-round defeat to Chelsea in which both managers made eight changes to their starting lineups.

Van Dijk played the entirety of the Netherlands' win over Germany on Saturday and then returned to Liverpool -- missing Tuesday's friendly with Belgium.

Koeman later revealed that the medical staff of Liverpool and the Dutch national team had reached an agreement for Van Dijk to only play in the UEFA Nations League clash with Germany. Koeman also said he believed Van Dijk would be "ready to play" against Huddersfield.

Regardless of these fresh fitness concerns, rotation is something that will have been on Klopp's mind as the trip to Huddersfield kick-starts a run of six games in 23 days for his Liverpool side.