Al Hilal coach Leonardo Jardim (AFP)
Jardim, whose team face Chelsea in the semi-finals at Mohammed Bin Zayed Stadium on Wednesday, said the odds are further stacked against the other sides because of the congested schedule.
"It's unfair that some teams have to play four matches in eight days and other teams are the best and only have to play two matches and are well rested," Jardim told a press conference Tuesday.
"I think there should be better care with the schedule, with more days to recover so teams from Asia (and North and Central America) have a better chance."
Saudi Arabia's Al Hilal, the record four-time Asian champions, thrashed UAE Pro League winners Al Jazira 6-1 in the second round on Sunday, the biggest win in the competition's history.
Jardim, who led Monaco to the Ligue 1 title in 2017, said his team benefited from playing an Al Jazira side that tired in the second half having beaten AS Pirae of Tahiti just three days earlier.
"I'm sure that European teams, and in this case Chelsea, they are always the favourites, no doubt about it, but they have an extra advantage when we have just two days to recover," said Jardim.
"They have a full squad that is fresh. Our victory from the other match is a reflection of two days earlier because Al Jazira had played a game two days before.
"I think the game would have been different had Al Jazira been rested."
African champions Al Ahly take on Copa Libertadores winners Palmeiras later on Tuesday in the first semi-final. Egyptian giants Al Ahly beat Mexico's Monterrey 1-0 on Saturday.
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