The Spanish coach, who took charge in early June, made his first appearance on the touchline on Monday as Ahly lost to Mexico’s Pachuca on penalties in a warm-up game.
Ahly will start their Club World Cup campaign against Inter Miami on Sunday 15 May in the tournament’s opening game.
“There hasn’t been enough time to prepare, but the team and I are ready for the challenge,” Riveiro told reporters after Monday’s match.
“We face Inter Miami in just a few days, and no one will talk about preparation if we lose. Expectations are high – fans want performances and results.”
The former Orlando Pirates boss praised his players’ effort in the friendly despite the defeat, and acknowledged the quality of the opposition.
“We gave our best against Pachuca, but they are a strong side and it was a tough match,” he said. “We need to keep working and improve our performance ahead of the World Cup.”
Riveiro also singled out new signing Ahmed ‘Zizo’ Sayed for praise.
The midfielder, who joined from Cairo rivals Zamalek on Friday, played the final 35 minutes and scored Ahly’s opening penalty in the shootout.
“Zizo showed his willingness to contribute and is ready to play. His integration into the squad has been positive,” Riveiro concluded.
Ahly were drawn in Group A alongside Inter Miami, Brazilin side Palmeiras and Portuguese champions Porto.
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