Morocco coach Herve Renard expressed his unhappiness at the absence of any water breaks in Sunday's 1-0 win over Namibia after Africa Cup of Nations organisers said an extreme heat policy would be in place amid sweltering temperatures in Egypt.

"Why were the players not allowed to drink during the first half and the second half? How is it possible?" asked Renard, after a late own goal from Itamunua Keimuine gave Morocco victory in their opening game in Cairo.

"I was very surprised. Strange. If you play football you know you need to drink something, especially after 20 to 25 minutes.

"So please the organisers they need to think about it, think about the players. The players are making the show. It's not us in the stands, it's not us on the bench, it's the players that are making the show."

The opening match in Group D kicked off at 4.30pm local time (1430 GMT) with the temperature hitting 37 Celsius (98.6 Fahrenheit) during the encounter at Al Salam Stadium.

"It's very, very hot today because it's in the middle of the day, there is not much air and ... it's very, very difficult," said Morocco midfielder Mbark Boussoufa.

The tournament's medical committee had announced before the start of the competition there would be two breaks in matches, in the 30th and 75th minutes, to allow players to rehydrate and apply cold towels.

Nigeria forward Samuel Kalu was hospitalised earlier in the week after collapsing during training due to dehydration, and missed his team's first match against Burundi on Saturday.