Ghana midfielder Christian Atsu has been ruled out FC Porto's league match against his former side Rio Ave on Saturday due to a thigh injury.
The hugely-talented player is said to have contracted an adductor muscle in his left thigh.
Atsu suffered the setback in training and he will not be available for head coach Vitor Pereira.
He was impressive as a second half substitute in the 1-0 win over Malaga in the UEFA Champions League round 16 first leg tie in midweek.
The winger has been impressive since returning from the Africa Cup of Nations.
Atsu has made 11 appearances for Porto this term and scored one goal.
He played last season on loan at Rio Ave where he was named Player of the Year.