Al Ittihad and Al Ahli set up an all-Jeddah Asian Champions League semi-final after they secured their passage in vastly different circumstances.
Two-time champion Al Ittihad had to rely on Fahad Al Muwallad's 78th-minute deflected strike to send it through 5-4 on aggregate against Chinese champion Guangzhou Evergrande.
Evergrande, coached by former World Cup-winning boss Marcello Lippi, had been minutes away from qualifying after Lucas Barrios (19th) and a 35th-minute Dario Conca penalty cancelled out Al Ittihad's 4-2 first-leg lead.
That would have been enough to send the Chinese through on away goals but Al Muwallad popped up late, following a rare attack from the Saudi side, to rob the hosts.
"Football can be very cruel at times and unfair," Lippi told the official Asian Football Confederation website www.the-afc.com.
"We have worked all year to become better and to reach our objectives and we came to the ACL with one objective. But I believe we should have passed this round.
"We played well and had plenty of chances to score. Unfortunately we have been eliminated and I want to thank the players for their efforts in this game, they have been playing like a team."
Al Ahli was far more comfortable as it romped to a 4-1 second-leg success over Sepahan and progress after the opening tie was goalless.
Al Ahli's hopes of going through were boosted by the dismissal of Sepahan goalkeeper Reza Mohammadi on 27 minutes.
Victor Simoes converted the resultant penalty before Amad Al Hosni added a second on 25 minutes.
A Kamel Al Mor own goal two minutes later gave the Iranian side brief hope but Al Hosni grabbed his second in first-half injury time before Abdulrahim Jaizawi confirmed the win on 69 minutes.
A third Saudi side, Al Hilal, will attempt to reach the last four when it tries to overturn a 1-0 deficit at home to Ulsan Hyundai.
In the other quarter-final Uzbekistan's Bunyodkor is in the box seat having drawn 2-2 at A-league side Adelaide United in the first leg.
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