Salem Al-Dawsari's late goal secured Saudi Arabia a first World Cup win in 24 years with a 2-1 victory over Egypt in Volgograd.
In what was a dead-rubber game in Group A after both teams lost their opening two games, Mohamed Salah, who was not initially named in Egypt's starting line-up, gave his side the lead in the 22nd minute, scoring his 50th goal in 58 appearances for club and country since July 2017.
Essam El-Hadary, who become the oldest player to feature in a World Cup aged 45 years and 16 days, saved Fahad Al Muwallad's 41st-minute penalty but he could not keep out Salman Al Faraj's spot-kick deep into first-half injury time as Saudi Arabia drew level.
The game was seemingly heading for a draw when Al-Dawsari struck to spark wild celebrations from Saudi Arabia as they ended their World Cup campaign with victory, while Egypt, who finished fourth in group A, became the first side since Honduras in 2014 to lose all three group games at a World Cup.
There was confusion before kick-off when Salah was initially left out of Egypt's starting line-up.
The Liverpool star was eventually included in the line-up minutes after an earlier tweet was published with a list omitting the 26-year-old's name.
Salah's presence had been the subject of speculation following media reports he was on the verge of quitting international football but he put all that behind him in the 22nd minute, bringing down Abdalla El Said's long ball before lofting it over the onrushing Yasser Al Mosailem and into the back of the net for his second goal of the tournament.
It was Egypt's first goal from open play at a World Cup since 1934 and Salah, who converted a penalty against Russia in their second group game, should have doubled the advantage minutes later.
He broke clear on goal but, after drawing Al Mosailem, uncharacteristically dinked wide of the right-hand post.
The other major story was the inclusion El-Hadary, who smashed the record set by Colombia goalkeeper Faryd Mondragon - who was aged 43 years and three days when he played against Japan in Brazil in 2014 - to become the oldest player to feature at a World Cup.
He justified his inclusion in the 41st minute, flying to his right to push Al Muwallad's powerful penalty onto the crossbar after Yasser Al-Shahrani's cross had hit Ahmed Fathy's arm.
However, he could not do anything to preserve his side's lead when Saudi Arabia were awarded a penalty deep into first-half stoppage time as Fahad appeared to pull the shirt of the covering Ali Gabr before going down in a heap.
But after a VAR-induced review that took almost five minutes to complete, Colombian referee Wilmar Roldan decided to stick with his original decision.
It was second time lucky from the spot as Salman Al-Faraj took responsibility from 12 yards and El-Hadary could not repeat his heroics as the first-half clock ticked past 51 minutes.
After the break, El-Hadary made an acrobatic save to keep out Housain Al-Moqahwi's header but chances were few and far between as the game looked to be heading for a draw.
However, in the fifth minute of second-half injury-time, Al-Dawsari popped up in the box to volley past El-Hadary with the last kick of the match to secure a famous Saudi win.