Iraq were one of three teams to finish the group stage with maximum points, along with defending champions Qatar and Iran, with Casas's side delivering the biggest upset of the tournament so far when they beat Asia's top-ranked side Japan.

Iraq play Jordan in the last 16 on Monday and although Casas said his side drew confidence from the memorable victory over Japan, the Spaniard added that there was a long way to go in the tournament.

"We aren't favourites. I repeat, we're very happy with our tournament until now. The Iraqi people are very proud of the players and their performances," Casas told reporters.

"But tomorrow we have a very hard match against a very good team. In one match, all is possible - one red card, one penalty, one mistake or nerves. So we aren't favourites for sure.

"We can win all matches but we need to give 200%. If we have a perfect match it's possible to win but if you make one mistake (in the knockout stage) you say 'Bye, bye'. All is possible in football but it's very hard."

Jordan also impressed in the group stage with a 4-0 win over Malaysia and a 2-2 draw with South Korea, who were one of the pre-tournament favourites.

Hussein Ammouta's side earned praise for how they pressed as a unit against South Korea, especially their forward line, while they regularly won duels all across the pitch.

"We are very similar in our style. Jordan are a very good team, it won't be easy," Casas said.

"I think Jordan and us are on the same level. Jordan have a very good coach. They have three strikers who are very dangerous. We have a lot of good things too.

"Obviously we have confidence after three matches but it's not enough. It was amazing when we beat Japan but it was only one match. To win the Asian Cup we have to win four more matches; we have possibilities but it's not easy."