Real Madrid striker Ronaldo is ruled out of action for up to two weeks after sustaining a calf injury, the Spanish Primera club said in a statement on Friday.

The Brazilian international was injured during Real's training session on Thursday and will be sidelined from 10 to 14 days, the club's official website reported.

Ronaldo will miss Real King's Cup last 16 clash against Athletic Bilbao on the third of January and is doubtful for Primera Liga clash against Villarreal five days later.

The news will come as a blow to caretaker manager Juan Lopez Caro who has already lost the services of striker Raul who suffered a serious knee injury in November.

Ronaldo played 17 matches for Real this season and scored nine goals in all competitions.