Cristiano Ronaldo scored a stunning winner on Tuesday as Al-Nassr came back to beat visitors Al-Shabab 3-2 and put Al-Ittihad's Saudi Pro League title celebrations on hold.
Al-Ittihad remain favourites to clinch the title with two games remaining in the season after beating Al-Batin 1-0 through Romarinho's header in the ninth minute.
The Jeddah club remain top of the league with 66 points, three ahead of Al-Nassr and hold the advantage in the head-to-head between the two clubs, the first tiebreaker if they finish level on points.
In Riyadh, Al-Nassr fans had watched in disbelief as their team conceded two Cristian Guanca goals, the first from a penalty, within 40 minutes of the start at Al-Awwal Park.
Brazilian Talisca revived Al-Nassr's hopes of staying in the title race one minute before halftime and Abdel-Rahman Ghareeb levelled the scores six minutes after the break.
Ronaldo completed the comeback win with a curling shot from just from outside the box in the 59th minute and was immediately mobbed by his teammates.
The Portuguese striker then broke away and prostrated himself with his head on the turf in an imitation of the pose Muslims adopt for prayer.
"The team played a fantastic game. Being behind 2-0 is very difficult but we believed till the end and we scored three goals," Ronaldo told SSC TV.
Al-Ittihad goalkeeper Marcelo Grohe was visibly disappointed when fans informed him of the final score at Al-Nassr but his club can clinch their first league title since 2009 if they beat 12th-placed Al-Feiha next Saturday.