The group stage of the western half of the continent's premier club competition resumed in Qatar on Monday after a seven-month coronavirus shutdown.
The second matchday started with another positive test for COVID-19 that robbed Al Sadd of winger Saoud Al-Nasr but the former Asian champions twice came from behind against Al Ain at an empty Jassim Bin Hamad Stadium. Qatar winger Akram Afif and former Arsenal midfielder Santi Cazorla got Xavi Hernandez's side back on level terms before Baghdad Bounedjah put them in front, only for Boualem Khoukhi to head into his own net in the 67th minute to hand Al Ain a point.
Morocco striker Abderrazak Hamdallah scored twice as Al Nassr took full advantage to top the group by two points from Al Sadd, with Sepahan third on three points and 2003 champions Al Ain rock bottom with a single point.
At the new Education City Stadium, defender Shojae Khalilzadeh lashed the ball into the net from an 83rd-minute corner to give Iran's Persepolis a valuable 1-0 win over Group C leaders Al Taawoun.
Saudi club Al Taawoun still top the group but are now level on points with Qatar Stars League champions Al Duhail, who earlier comfortably beat Emirati outfit Sharjah 2-1 at the same venue, which has been built for the 2022 World Cup.
Matches in the four East Asian groups resume in a hub in Malaysia in October. The final will be in Doha on Dec. 19. (Writing by Nick Mulvenney; Editing by Christopher Cushing)