Barcelona's Lamine Yamal sparked strong reactions online after waving a Palestinian flag during the team's victory parade.
The 18-year-old, who's widely regarded as one of the world's best players, joined his teammates on an open-top bus on Monday.
He held the flag as they were driven through the streets of Barcelona to celebrate winning Spain's La Liga football title.
Coach Hansi Flick, when asked about Yamal waving the flag, said on Tuesday: "This, I don't normally like.
"I spoke with him. I said if he wants this, it is his decision. He is old enough. He's 18 years old."
Yamal, who is Muslim, also posted pictures of himself holding the Palestinian flag on his Instagram account.
Nearly 750,000 people are estimated to have taken to the streets to celebrate Barcelona's La Liga title win.
Last month, Yamal suffered a hamstring injury and did not play against Real Madrid at Camp Nou on 10 May, the match which officially sealed the La Liga title.
There has been a global backlash by some against Israel over the humanitarian toll of the war in Gaza, which has spread to sport and culture.
Protests have been seen in football, cycling, and basketball.
Spain is one of five countries boycotting this year's Eurovision song contest to protest Israel's inclusion.
During a news conference on Tuesday, Mr Flick said celebrations with fans after back-to-back titles was his priority.
"We are playing football and you can see what the people expect from us," he said.
"We are playing football to make the people happy. This is for me the first thing we have to do."
Read more from Sky News:
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Israel's Eurovision song sparks debate
Yamal, whose father is Moroccan, is one of the leading contenders to take over from Lionel Messi and Cristiano Ronaldo as football's biggest star.
Despite his injury, he is still expected to make an appearance when the World Cup is held in the US, Canada, and Mexico in June and July.
(c) Sky News 2026: Barcelona boss Hansi Flick reacts after Lamine Yamal waves Palestinian flag at La Liga v
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