Cristiano Ronaldo has sustained a muscle injury in his left thigh, Real Madrid announced Thursday, making the Portuguese striker a doubt for next week's King's Cup final against Barcelona.

According to the AS newspaper website, Ronaldo could be out for two weeks, which would mean him missing the King's Cup final in Valencia on Wednesday as well as the Champions League semifinal first leg the following week.

Ronaldo, scorer of 28 league goals this season, didn't play in Real's 4-0 La Liga victory over Real Sociedad on Saturday or Tuesday's 2-0 defeat by Borussia Dortmund in the Champions League quarterfinal second leg, officially because of a left knee injury.

Real, third in La Liga behind city rivals Atletico Madrid and Barcelona, host Almeria on Saturday in league action.