Two late goals saw Al-Ettifaq upset Al-Ahli in their final home game of the Saudi Pro League season, winning 3-1 at King Abdullah Sports City Stadium on Thursday.
Top scorer Ivan Toney won and converted an early penalty to seemingly set Al-Ahli on course for their ninth win in 10 matches in all competitions.
But that lead was cancelled out four minutes after half-time as Mohammed Abdulrahman netted for Al-Ettifaq.
And with only three minutes remaining, the visitors turned the match on its head as Toney's former Newcastle United team-mate Georginio Wijnaldum was felled by Edouard Mendy.
Wijnaldum, like Toney, took the spot-kick himself and, like Toney, found the net, before substitute Madallah Al Olayan wrapped up the points from a tight angle in the 95th minute.
Defeat threatens to end Al-Ahli's season on a dampener less than a month on from their AFC Champions League Elite final triumph over Kawasaki Frontale.
Fifth in the table but at least assured of ACL Elite qualification as the holders, they finish their campaign at mid-table Al-Riyadh on Monday.
Data debrief: Familiar failings haunt Al-Ahli
Al-Ahli have led for the most minutes in the Saudi Pro League this season and quickly hit the front again through Toney's sixth-minute penalty.
Ivan Toney's now at 22 goals, just 2 away from Cristiano Ronaldo at the top of the #RoshnSaudiLeague scoring charts pic.twitter.com/UPoY76tKno
— Roshn Saudi League (@SPL_EN) May 22, 2025
But protecting those leads has proven a bigger issue, and again the Asian champions could not hold on for all three points.
Indeed, having conceded an equaliser early in the second half, the two late goals mean Al-Ahli have now dropped 15 points from winning positions this season.
Given they are 16 points off top spot, this has been a damaging trend.