Portugal captain Cristiano Ronaldo will travel to Spain for treatment on a hamstring injury that is "more serious" than first thought.
The 41-year-old forward, who has scored 21 goals in 22 games this season in the Saudi Pro League for leaders Al-Nassr, was substituted in a 3-1 win against Al-Fayha on Saturday.
He had earlier missed a penalty.
Speaking before the side's match against Neom on Saturday, Al-Nassr coach Jorge Jesus said Ronaldo would visit Madrid where "he will need treatment from his personal physiotherapist".
"In the last game, Cristiano left with a muscle injury. After the tests he underwent, it became clear that it is a more serious injury than we were expecting," he added.
"He will need rest and recovery. We hope he will return soon to help the team."
It is unclear whether the five-time Ballon d'Or winner will be fit to play in Portugal's friendlies against Mexico on 29 March and the United States on 1 April.
Ronaldo, who has scored 965 career goals, has said he will not retire until he notches his 1,000th.
His injury comes a month after he returned to the Al-Nassr side having missed three games amid doubts over his future with them.
He had reportedly been unhappy with how the club were being run by Saudi Arabia's Public Investment Fund.
Ronaldo moved to the Middle East in December 2022, shortly after his contract with Manchester United was terminated by mutual agreement following an interview in which he criticised the club.
The switch saw him become the best-paid player in football history with an annual salary of £177m and he signed a new two-year contract in June.