When the United States steps on the field for a group stage game against Australia on Friday afternoon, there's a chance Christian Pulisic won't be on the field.

The men's national team star aggravated a calf strain suffered earlier in the week during the first half of a 4-1 win over Paraguay and has been limited in practice. After missing Tuesday's training session, Pulisic worked off to the side with a trainer on Wednesday, marking an improvement in his recovery.

However, he's still not practicing with the team, which indicates there's a chance he might not be fit enough to play on Friday afternoon.

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Among the players that could step in for Pulisic if he isn't able to go are Borussia Mönchengladbach midfielder Giovanni Reyna, America attacker Alejandro Zendejas, Marseille's Timothy Weah and Leeds United's Brenden Aaronson.

The latter made it clear he won't be making any changes to his normal preparation.

"I'm the type of guy that I'm always trying to be as calm as possible. I don't let any of the emotions of the game get to me at all," Aaronson said.

"I kind of take it day by day, and you know, if that opportunity comes, I'll always be ready. That's kind of where I am. I'm always ready to start games, play games, give my best and give my all. I'm looking at [it] the same way as it's a game to play and whatever role I'm given is I'm gonna give my best and it's just the player that I am."

The USMNT and Australia kick off at 3 p.m. ET on Friday.

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