Star striker Abderrazak Hamdallah set up Abdulfattah Asiri’s 54th minute opener before sealing the points with a late goal of his own as Mano Manezes’ side climbed to eight points from four matches, one clear of Al-Sadd SC, who beat Al-Wehdat across town in Friday's other Group D clash.
Foolad’s first defeat in the competition leaves the Iranian club three points adrift of top spot, with Monday’s clash against Al-Sadd now looming as a must-win proposition.
The win means Al-Nassr could theoretically have won the group by the end of Monday’s match against Al-Wehdat of Jordan, but wrapping the section up that quickly will depend on the outcome of Foolad’s crucial meeting with Al-Sadd.