The United States have confirmed that forward Christian Pulisic fractured his leg during his side's 4-1 defeat by Belgium in the World Cup last 16.

Pulisic was substituted in the 59th minute just moments after Belgium scored their third goal in Seattle.

The 27-year-old appeared to sustain the injury early in the second half while attempting a shot, instead kicking the back of Belgium midfielder Youri Tielemans' leg.

"Christian Pulisic has been diagnosed with a microfracture and bone bruise of the tibia/fibula in his right leg suffered during the match against Belgium," said a US Soccer federation statement on social media.

US Soccer and Pulisic's club team, AC Milan, will collaborate on his recovery plan.

The US players were widely criticised in the US media after suffering elimination with their heaviest World Cup defeat in 36 years, with Pulisic's early withdrawal questioned.

"I was a bit disappointed in Christian Pulisic. Whether he wants to be the star of this team or not, we didn't see enough from him in this particular game - and, really, the whole World Cup. Little glimpses here and there," said the US' all-time leading goal scorer Carli Lloyd.

Recalling Pulisic's decision to sit out the Gold Cup in 2025 in order to rest and recover before a World Cup year, she posted on X: "You rest when your playing career is over. Period."

Landon Donovan, the all-time US top scorer at men's World Cups, said: "I would have punched the doctor in the face and said, 'You're not taking me off the field'."

While US Soccer did not give a timeframe for Pulisic's recovery, he would not have been able to play had his side progressed to the quarter-finals.

The Athletic reported that Pulisic "will be sidelined for several weeks but not months," citing multiple people briefed on the diagnosis.

AC Milan begin their Serie A campaign on 23 August against Torino.