Cristiano Ronaldo's Al Nassr booked their place in the Asian Champions League knockout stages on Monday with a 0-0 draw at home to Iran's Persepolis.

The Saudi Arabian side, who had won all four Group E matches going into the encounter in Riyadh, needed only a point at Al Awwal Park to advance to the last 16.

Nassr got just that, although they played the majority of the match with 10 men.

Their celebrations were also dampened somewhat by Ronaldo's substitution with 13 minutes remaining following an earlier collision with Persepolis goalkeeper Alireza Beiranvand.

The contest sparked into life on four minutes, when Nassr had a claim for a penalty denied after Ronaldo looked to have been tripped in the visitors' area. However, the Portugal forward admitted to the referee that it was not foul, with the official upholding the decision after consulting VAR.

Things worsened for the hosts not long after when Ali Lajami was shown a straight red card on 17 minutes for a raking his studs down Milad Sarlak's shin.

Persepolis, two-time runners-up, did have a goal disallowed at the start of the second half, while Ronaldo later turned sharply inside the Persepolis penalty area but fired his low shot wide.

The Nassr captain, 38, had appeared to injure his neck at the beginning of the second half after Beiranvand landed on him when coming to claim a high ball.

Ronaldo was withdrawn on 77 minutes seemingly experiencing some discomfort.

Nassr face arch-rivals Al Hilal on Friday in a top-of-the-table clash in the Saudi Pro League.

In the group's other match, Al Duhail got their first win this campaign with a 2-0 victory at home to Tajikistan side Istiklol.

In Group C, Saudi Arabian champions Al Ittihad bounced back from defeat in round four with a 2-1 win at Uzbekistan's AGMK FC.

Moroccan Abderrazzaq Hamdallah scored twice in four first-half minutes before Martin Baokye pulled one back for the hosts with 12 minutes remaining.

The win means two-time winners Ittihad, who had new manager Marcelo Gallardo making his Asian Champions League debut, remain top of the standings heading into next week's tie at home with second-placed Sepahan.

The Iranians defeated Iraqi opponents Air Force Club 1-0 on Monday at the Azadi Stadium - despite having two men sent off - to move two points behind Ittihad.

Meanwhile, there remains all to play for in Group B after Uzbekistan's Nasaf Qarshi moved top with a 3-1 win at home to Jordan's Al Faisaly, and Qatari side Al Sadd defeated Sharjah 2-0 in the UAE.

Nasaf sit at the summit on 10 points ahead of their final match next week against Al Sadd, who are third on seven points. Sharjah lie second on eight points.

The group stage, which this year returned to a home-and-away format for the first time since early 2020, runs until mid-December, with the 10 pool winners and the six best second-placed teams advancing to the knockout rounds starting in February.

The final takes place, across two legs, in May.