Explained: Why Cristiano Ronaldo is not playing for Al-Nassr in AFC Champions League clash at Al Shorta – with 900-goal Portuguese superstar not making trip to Iraq

Ronaldo's absence will be a significant blow for Al-Nassr, who have struggled to get going in this campaign and have already dropped four points in the first three matches of the Saudi Pro League. The Portuguese striker has been diagnosed with a viral infection and has been advised to rest in Riyadh.

On Sunday, Al-Nassr released an official statement which read: "Al-Nassr captain Cristiano Ronaldo wasn't feeling well today and was diagnosed with a viral infection. The team's doctor confirmed he needs to rest and stay at his place. As a result, he will not be travelling with the team to Iraq today. We wish a speedy recovery to our captain."

Even as Ronaldo sits out the upcoming match, the 38-year-old continues to chase historic milestones. After his 900th career goal against Croatia, the Portuguese icon added yet another against Scotland. As he approaches the twilight of his career, Ronaldo has set his sights on reaching the unprecedented landmark of 1,000 career goals before retiring and if he keeps going at this pace, it might even get conquered. He has already scored five goals in four matches across all competitions for Al-Nassr this season and his recent form in the international break suggests that the 39-year-old is still a long way from hanging up his boots.

Ronaldo should be able to return to action next Friday against Al-Ettifaq in the Pro League, provided he recovers from the viral infection in time.