The 41-year-old, who has netted 21 goals in 22 games this season in the SPL, was injured in a 3-1 win over Al-Fayha on Saturday.
"After examining Ronaldo’s injury, it became clear that he needs a period of rest and treatment, so we decided to send him to Spain," Jesus told a press conference.
"The medical staff diagnosed Ronaldo’s condition and confirmed that he is unable to take part in tomorrow’s match or the following one (against Al‑Khaleej)".
It remains unclear whether the five-time Ballon d'Or winner will be fit to participate in Portugal's friendlies against Mexico on March 29 and the US on April 1.