French team the Catalans Dragons are investigating complaints stadium security asked fans to remove rainbow flags during Israel Folau's try-scoring debut for the French Super League side on Saturday.
The Dragons have drawn much criticism within rugby league for signing the 30-year-old Folau, whose Wallabies contract was terminated last year after he posted a meme on social media that said hell awaits "homosexuals" and other groups.
Folau took just six minutes to score his first try for the Dragons and received a warm reception from home fans at the Stade Gilbert Brutus in Perpignan during a 36-18 win over Castleford Tigers.
There were no organised protests but Castleford fans complained security had asked them to put away their rainbow flags. The flags are symbols of the LGBT movement and more generally, tolerance and inclusion.
"We were told by about five people [who] came to us and told us were weren't allowed to have the flags," one woman fan told Sky Sports.
"They then came back to us later on and said it was against the views of the [Catalans] club for us to have the flags."
The Dragons said it was not their policy to ban rainbow flags.
"It is not forbidden. We are gathering more information about what happened," the team said in a statement published by British media.
Folau, a fundamentalist Christian, scored 37 tries for the Wallabies before he was sacked by Rugby Australia.
His signing by the Dragons sparked outrage within the rugby league community, with Super League executive chairman Robert Elstone calling it a "sad day" for the competition.
On Saturday, in his first rugby league match for a decade, Folau drew cheers when he rose to take a trademark high catch on the try-line for his early score.
Dragons fans in the crowd of 8,886 chanted "Izzy! Izzy!" as he was mobbed by his team mates.
He almost scored a second before halftime.
At the end of the match, Folau held up his hands to the crowd in appreciation before stopping to take selfies and chat with supporters.
This month, the Super League's board voted to ensure they had greater authority over stopping similar "controversial signings".
Folau will play his first match in England against Hull at the beginning of March.
Dragons coach Steve McNamara declined to comment on the flag matter in his post-match media conference.
"I am here to talk about rugby league. That is what I know, that is what I do, not any of the other stuff," he said.
"We have signed a very talented player and he showed that today. Everybody deserves a second chance.
"When I sign a player I judge him on his playing abilities, not on his religious or political beliefs.
"I hope we can move on now and just concentrate on the rugby league."