Chelsea defender Baba Rahman faces prolonged time on the sidelines

Chelsea defender Baba Rahman faces a longer spell on the sidelines after doctors revised their recovery date for the Ghana international's return from his knee injury setback.

The revision of the date for the return of the left-back has also forced German side Schalke to alter their plans of signing the defender for another loan spell from the English side.

Schalke have announced that their plans to extend defender Rahman's loan from Chelsea will depend on his recovery from the knee injury which is expected to take longer than the expected August return date.

Ghana international spent last season on loan at the Bundesliga side, but has been out of action since he was injured at the African Nations Cup.

The left-back made 21 appearances for the Royal Blues before suffering an anterior cruciate ligament tear.

Schalke have now revealed that the return date for Rahman has changed after latest analysis from doctors.

"Our team doctor met Abdul in London. His knee injury is more complex and [his recovery] might be prolonged," Schalke sporting executive Christian Heidel told Bild.

"We will wait another four weeks and then decide with Baba and his agent whether [another loan] makes sense."

The 22-year-old suffered an anterior cruciate ligament injury in his left knee in January while playing for Ghana in the Africa Cup of Nations, however, he was expected to be match fit for August following a successful rehabilitation.

Baba joined Chelsea for £14m from Augsburg in 2015 but struggled to make an impression on Jose Mourinho then Antonio Conte, who brought in Marcos Alonso.

Schalke had reached an agreement with both Chelsea and the player to extend the loan.

Schalke signed him on loan last year only to see his season cut short in January.

Chelsea are keen to see how he returns as they believe he still has the potential to succeed in the Premier League.

However, playing regular competitive football in the Bundesliga is considered the next best step.