Video footage emerged of Al-Shamrani spitting at Western Sydney Wanderers defender Matthew Spiranovic, who he also headbutted, following Al-Hilal's Champions League loss at the King Fahd International Stadium in Riyadh on November 1.
The AFC Disciplinary Committee responded on Saturday by suspending the Al-Hilal striker for eight Champions League matches after violating Article 57 of the Disciplinary Code.
The Saudi Arabian veteran insisted he was provoked by Spiranovic, while claiming spitting was a "normal" reaction.
"Actually I was provoked by the Western Sydney player, and it's a normal reaction for a player sometimes it happens," Al-Shamrani said.
"He used abusive words and it was unsportsmanlike conduct that provoked me. For him, he was supposed to cool down as his team already won and not use such words or language against me which really provoked me."
