South Korea coach Paulo Bento hopes Neymar is fit to play his team in their World Cup last-16 clash with Brazil, even if he concedes it would better for them if he was absent.

The Taeguk Warriors caused something of a shock by reaching the first knockout round of the tournament at the expense of Uruguay, with South Korea scoring a dramatic winner against Portugal on matchday three.

Brazil await in the last 16 and there remains some doubt over the fitness of talisman Neymar, who injured his ankle in the Selecao's first match of the tournament.

Neymar's involvement will be determined in training on Sunday, and Bento hopes he is ultimately passed fit.

"It would be hypocritical if I said that it's better to play against Neymar than without him, but to be fair, I always prefer the best players to be on the field. If not, we hope it's not because of injury, that's for sure," he said.

"It will be up to the coach, Tite, to decide whether he's in the starting line-up if he's fit to play, and we'll design the best strategy to play against a great national team that is full of balance and adding more and more talented players."

Nevertheless, Bento clearly feels South Korea's chances of causing an upset have not been helped by FIFA.

The Portuguese coach vented his frustration at the governing body scheduling games just 72 hours apart, particularly given the emotional exhaustion from their turnaround against Portugal.

"Unfortunately, we don't have much time to train, because 72 hours is too little, I doubt any team can do that," he added.

"After physical tiredness, and the emotional fatigue, we let the players rest [on Saturday] and only trained this morning, and of course that's a burden for the team.

"We have an additional burden compared to Brazil because they changed their line-up in the last game.

"They did something we couldn't do in the last game and honestly speaking, I was watching the 2018 World Cup and after the group stage, I do not remember seeing games played after 72 hours. The spaces between games was longer.

"In my opinion it's not fair to play every 72 hours, it's something inhuman, it's something FIFA intends to create less conditions for those who already have less conditions, but we need to accept it if it's FIFA's decision.

"It's difficult to play very a great team such as Brazil, who in my opinion they are the favourites, and if we add this burden, our task will be very difficult."

But as irritated as Bento was by FIFA's decisions, he certainly is not worried about motivation.

"I'm a realist. I conveyed we have a tough task ahead of us, but we have to try," he said. "If they needed me to motivate them for a last-16 game at the World Cup, they'd be in a bad spot.

"What they showed already shows they are motivated. I get more motivation from them than they get from me."