Cristiano Ronaldo missed Al Nassr's key Champions League clash, sparking speculation. Coach Stefano Pioli has now explained why.

Amid growing speculation on social media about Cristiano Ronaldo's presence in Iran for Al Nassr's AFC Champions League clash against Esteghlal, head coach Stefano Pioli addressed whether the Portuguese star will be available for the match.

Esteghlal and Al Nassr played out a goalless draw in the first leg of their AFC Champions League Elite Round of 16 match at the Azadi Sports Complex on Monday. It was a tale of two halves, as both teams had their fair share of chances but failed to convert any into a goal.

Jhon Duran hit a post and was thwarted by an inspired goalkeeping display as Al Nassr drew 0-0 in Iran without Cristiano Ronaldo.

Cristiano Ronaldo was absent as Al-Nassr and Esteghlal played to a 0-0 draw in the AFC Champions League Elite second round. Despite Jhon Duran's efforts and Sadio Mane's opportunities, Esteghlal's goalkeeper kept a clean sheet.

Cristiano Ronaldo’s Al Nassr finished third in their group (B) in the league phase, accumulating 17 points. Esteghlal FC, also in the same group as Al Nassr, finished sixth with nine points

Abdullah Al-Yazidi earned Qatar's Al-Sadd a 1-1 draw with Al-Wasl in Dubai in the first leg of their Asian Champions League Elite last 16 clash on Monday as Al-Nassr, missing Cristiano Ronaldo, were held to a 0-0 draw by Iran's Esteghlal in Tehran.

Meanwhile, Al Wasl -- who are featuring in the knockout round in the ACL era for the first time -- may not be as illustrious an outfit as their opponents, but their success has been based on being a well-drilled and settled side.

Al Nassr captain Cristiano Ronaldo has been left out of the matchday squad for their AFC Champions League clash against Esteghlal. Ronaldo did not travel to Tehran with the rest of his teammates for the first leg of the last-16 tie.