"The club would like to offer its sincere condolences to the family of the player.
Benitez had recently joined the club from Club America for three seasons.
The player participated for the first time with the team during yesterday's match against Qatar Sports Club in the Sheikh Jassem Cup without complaining of any health problems.
His sudden departure is a big shock for each member of the technical and administrative staff.
He was a player that over the short period he was here was regarded for his high moral character."
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It will be another misty and cloudy start to the day.
Another rather cloudy day, with the easterly wind continuing to bring low cloud in from the North Sea.
Some mist and hill fog tonight. Brightening up on Thursday.