Christian Pulisic is the star name in the United States of America squad - but they may have to find a way to win without him when they take on Australia on Friday.
Kick-off in the Group D clash at Lumen Field in Seattle is set for noon local time (8pm UK time).
Both the United States and Australia will be looking to build on winning starts after seeing off Paraguay and Turkiye respectively in their opening games.
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What happened to Pulisic
Mauricio Pochettino will have been concerned to see Pulisic go off at the break in his side's 4-1 win, however.
Pulisic had been influential in helping his side blow the Paraguay away in a dominant first half, claiming the assist for Folarin Balogun's first goal.
Pulisic has trained in the days leading up to the United States' meeting with Australia, but only in a limited individual capacity.
The Milan forward was seen training way from his colleagues with members of the US medical team during a session held on Wednesday.
Pochettino was unable to confirm at his Thursday press conference whether or not Pulisic would be fit to play a part against the Socceroos.
He said: "He’s evolving. He’s much better from Friday. We will see. If he is not available for tomorrow, he will be available for the next game [against Turkiye next Friday]."
Pochettino went on: "When this type of thing happens, always it’s painful. Christian is strong and with a great mentality.
"He’s doing a fantastic effort to try and be ready as soon as possible."
Pennsylvania-born Pulisic has 87 international caps to his name, scoring 33 goals.
