Newcastle fans waves flags and banners ahead of the English Premier League football match between Newcastle United and Brentford at St James Park in Newcastle-upon-Tyne, north east England on September 16, 2023. AFP
The unnamed British man, who was with a friend, did not suffer life-threatening injuries in Monday's attack, a police source said.
"The 58-year-old man was approached by a group of people wearing hoods. They injured his arm and back. He was taken to hospital in Milan, which he will be able to leave shortly," the source said.
Police have launched an investigation into whether the attack was linked to the match or not.
Newcastle said they were "deeply concerned" and were "liaising with local authorities to understand the circumstances".
"Our thoughts are with the supporter and their family and we hope for a full and speedy recovery."
Italian club AC Milan host Newcastle on Tuesday in their opening game of the Champions League group stage.
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