Super League is investigating a claim from a Castleford Tigers fan that they were asked to remove a rainbow flag during Israel Folau's debut for Catalans Dragons.

Folau scored an early try on his first rugby league outing since 2010, helping the Dragons defeat Castleford 36-18 in Perpignan on Saturday.

It was Folau's first appearance since he was sacked by Rugby Australia (RA) last May for posting homophobic comments on social media.

A Tigers supporter at the venue revealed on Twitter they had been told they were not allowed a rainbow flag, which represents a symbol of LGBT pride.

A joint statement from Super League and the Rugby Football League read: "Everyone should have the right to respectfully express their views. We are investigating.

"We will receive a full report by the end of this weekend and have more details on Monday."

A Dragons spokesperson added: "Rainbow flags are not banned at our club. It is not forbidden. We are gathering more information about what happened."

Catalans' signing of Folau sparked plenty of controversy and Super League clubs voted to have "greater authority to stop controversial signings" earlier this month.

Folau reached a financial settlement with RA in December before switching codes to pen a one-year deal with the Dragons.

Catalans head coach Steve McNamara praised the player for handling the scrutiny surrounding him on debut.

"Well I've just congratulated him on that [media scrutiny] downstairs because it is different," he said. 

"It is different for this area, this region to have journalists from around the world chasing players around in cars and following people. 

"All the other bits that go with it, for the players to deal with that and come up with a performance like that is a credit to them.

"For him to play his first game of rugby league and only train for 10 days with the team in total, to come up with that sort of defensive performance really gives us encouragement going forward with him.

"I knew he was ready to play. I said I wouldn't risk him if he wasn't. There was no way we were going to do that just because it was a home game."