Egypt coach Hector Cuper says he hopes "everyone in Egypt is happy" that El Hadary beat the record of Colombia keeper Faryd Mondragon, who was 43 years and three days old when he appeared at Brazil 2014.
It was second time lucky from the spot as Salman Al-Faraj took responsibilty from 12 yards and El Hadary could not repeat his heroics as the first-half clock ticked past 51 minutes.
Egypt will crash out of the World Cup regardless of their result against Saudi Arabia.
The two teams continued to play out an end-to-end game in the second half, with El Hadary's athleticism continuing to belie his years as he made some impressive stops.
Nonetheless, Egypt's hordes of supporters roared on Salah whenever he got near the ball and he opened the scoring in the 22nd minute when he raced on to Abdallah Said's long pass and kept his cool to lob Saudi goalkeeper Yasser Al-Mosailem.
But after a VAR-induced review that took nearly five minutes to complete, Colombian referee Wilmar Roldan chose to stick with his original decision.
It was a odd decision and did not go unnoticed by World Cup fans.
36% of Saudi Arabia's goals at the World Cup have been scored from the penalty spot (4 of 11).
Salem Aldawsari scored the victor for the Saudis with nearly the last kick of the match, volleying past El Hadary from a tight angle inside the Egypt penalty area.
For Egypt, Mohammed Salah's injury that he received in the Champions League final has severely hampered his performance and has had a negative effect on the team.
Egypt and Saudi Arabia are both disappointed to be leaving the tournament this early on, both will want to give their fans something to celebrate.
After the restart, the intensity of the game dropped but Hattan Bahebri nearly put Saudi Arabia into the lead with a volley from an acute angle but his strike going just over the bar.
Mohamed El-Shenawy started Egypt's previous two matches.