The match fee was roughly double what he would get for a Premier League fixture, and this move is unprecedented until now.
However, it is set to be repeated in the future with Oliver and other top English officials.
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The new boss of the PGMOL, Howard Webb, is said to be more relaxed than his predecessors at the Football Association when it comes to handling requests from foreign associations, and sees the benefit of his officials working in other domestic leagues from both a reputational and experience perspective.
Oliver did not have a Champions League fixture this week, which allowed him to fly in and out of Riyadh in just over a day, giving him ample recovery time ahead of Liverpool versus Nottingham Forest on Saturday.
During the match, Oliver booked Cristiano Ronaldo when he hauled down an opponent by the neck.
Webb, who spent two years between 2015 and 2017 as the head of referees in Saudi Arabia, is keen to strengthen links between the PGMOL and overseas refereeing bodies.
Al-Nassr went on to lose the game 2-0, with former Manchester United striker Odion Ighalo scoring a brace, both coming from the penalty spot, to dent Ronaldo and Co’s title hopes.
It was Al-Nassr’s first game since sacking manager Rudi Garcia, with the match managed by former youth team coach Dinko Jelicic, who has taken over as interim boss.
