Arsenal manager Arsene Wenger has admitted that Alexis Sanchez may not be in the right mindset to play this weekend after the disappointment of missing out on the World Cup.
But Wenger said he has no doubts the Chile star will regain his focus quickly, and that players who carry "the expectation of a nation" must also be able to cope with the low points in their careers.
Sanchez's Chile failed to qualify for next summer's tournament in Russia after losing 3-0 to Brazil on Tuesday night, and the forward wasn't expected back in London until early Thursday evening.
Wenger said he will assess the player's physical and mental state on Friday, but admitted that he may not be able to start against Watford on Saturday.
"He is in a very difficult mind. Chile just won the Copa America twice, and now they don't even go to the World Cup," Wenger said. "Sanchez is 29 at the end of the year, so the next one he will be 33. He expected to go. Certainly it's a big disappointment for him."
Chile's setback has raised renewed doubts about Sanchez's commitment to Arsenal this season. The forward is widely expected to leave the club when his contract runs out next summer, but the World Cup would at least have given him added motivation to be at his best until then.However, Wenger said he had no fears that Sanchez will down tools completely.
"I have no doubt that he wants to perform. He never goes on the football pitch to lose a football game, never. Sanchez is a winner type," Wenger said. "To play at the top level as well, it is part of dealing with that kind of disappointment.
"If you want to make a big career it's a bit of a roller-coaster, because you are sometimes on a high then three days later you're on a low. It's part of our job. Some deal better than others with it. ... You have always to set targets when you're a football player. When one is gone, you focus on something else."
Aaron Ramsey's Wales also failed to qualify but Wenger acknowledged that the disappointment may be greater for Sanchez because of the weight of expectations back home.
"I would say you have in every generation a player who carries the pressure of expectation of a nation. Why? I don't really know. But it is like that. In France it was [Zinedine] Zidane. In England it was [David] Beckham ... In Chile it's Sanchez. In Argentina of course it's [Lionel] Messi.