The fireworks and euphoria that greeted Ronaldo's gala unveiling in January were in sharp contrast to the close of Al Nassr's season, when the Portuguese sat out a 3-0 win against Al Fateh late on Wednesday.
Despite signing the five-time Ballon d'Or-winner in a two-and-a-half-year deal said to total 400 million euros ($428 million), Al Nassr finished second in the Saudi Pro League without any silverware, although they qualified for the Asian Champions League as a consolation.
Ronaldo scored 14 goals including five penalties but it was a "disappointing season" for the Riyadh club, said Moqbel Al-Zabni, editor-in-chief of the Saudi capital's Al Riyadiah newspaper.
"They needed at least one championship."
Fan frustrations aside, however, the 38-year-old remains a marketing coup for Saudi football and the wider country, which is attempting to reinvent itself as a magnet for tourism and foreign investment.
According to a source close to the negotiations, the major oil exporter is also about to land a "huge" deal for Ronaldo's ex-La Liga sparring partner Lionel Messi, the World Cup-winning Argentine icon.
Reports have linked a string of other big names to the Saudi Pro League thanks to the riches of the Public Investment Fund, the sovereign wealth vehicle behind LIV Golf and the purchase of Premier League club Newcastle United, as well as Ronaldo's signing.
Saudi Arabia is also considering bidding for the World Cup, following in the footsteps of its neighbour Qatar, and has already explored joining forces with Egypt and Greece to present a tri-continental option.
Saudi Arabia's lavish spending on sport is often criticised as "sportswashing" -- an attempt to shift the focus from its record on human rights.
The conservative monarchy executed 81 people in a single day last year, outlaws homosexuality and triggered international condemnation when journalist Jamal Khashoggi was murdered in the Saudi consulate in Istanbul in 2018.
Ronaldo has said little in public since arriving in Riyadh with his model girlfriend Georgina Rodriguez -- a highly bankable influencer with 49.5 million Instagram followers -- and five children.
After mistakenly calling the country "South Africa" when he was first welcomed at Al Nassr, last week he backed the Saudi Pro League to become one of the best in the world.
"Step by step, I think this league will be a top-five league in the world," he said in a post-match interview.
Although it quickly became clear that the veteran player could not win games single-handed, Saudi football has never enjoyed such attention.
Al Nassr's Twitter followers have jumped from 800,000 to more than four million, and swelled from two million to 14 million-plus on Instagram.
Women fans, barred from football stadiums until just a few years ago, have become a common sight, while Ronaldo has also drawn many families with children.
"Saudi football has become the talk of most international news agencies and media," Saudi writer Musaed Al-Abdali wrote in his column for Al Riyadiah.
Egyptian sports analyst Ahmed Afify said Ronaldo could not be blamed for the trophy-less season, pointing to injuries to other players including Colombian goalkeeper David Ospina.
"He (Ronaldo) showed great commitment and did not act like a big star towards his team-mates," Afify said.
However, some fans were not impressed with what they saw of Ronaldo, who sometimes appeared anonymous.
"In many matches it was difficult to locate him on the field," commented sports journalist Hawass Al-Ayed.
After Al Nassr drew against a modest Al Khaleej outfit two weeks ago, fan Mubarak Al-Shehri lashed out at Ronaldo's "bad and incomprehensible performance".
Another fan, Ibrahim Al-Suwailem, wearing the traditional Saudi white robes, questioned the decision to buy Ronaldo.
"Ronaldo alone is not enough," he said, adding: "Is it worth this huge amount? It's a deal for publicity, and the fans want championships at the end of the day."
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