Seven players from Australian National Rugby League team Manly Sea Eagles will boycott a championship match this week in protest at being made to wear an "inclusiveness" jersey, triggering criticism from the club's first openly gay player.

Manly coach Des Hasler said the players were opposed to wearing the pride jersey on "religious and cultural" grounds and would not play the team's home game against Sydney Roosters on Thursday.

"The players will not play on Thursday and we accept their decision," an emotional Hasler told reporters at a news conference on Tuesday.

"These young men are strong in their beliefs and their convictions and we will give them the space and the support they require."

Manly announced on Monday the team would wear the jersey which has rainbow bands as a symbol of "inclusiveness."

Former Manly great Ian Roberts, the first professional rugby league player to come out as gay, said the players' opposition to the jersey was "sad and uncomfortable."

"I can promise you every young kid on the northern beaches (of Sydney) who is dealing with their sexuality would have heard about this," he told Sydney's Daily Telegraph.

Hasler said Manly had mismanaged the well-intentioned jersey initiative by not consulting its players and had failed to adequately inform stakeholders inside and outside the club.

Reading from a prepared statement, he apologized on the club's behalf both to the players and to the "minority groups within the community who embrace the rainbow colors as a symbol of pride in who they are."

"The intent of the jersey was to support the advocacy and human rights pertaining to gender, race, culture, ability and LGBTQ movements," he said.

"Sadly the execution ... was poor."

Prior to Hasler's comments, NRL boss Peter V'landys said the league respected the players' position but hoped they would change their minds.

Australian Prime Minister Anthony Albanese earlier endorsed Manly's decision to wear the jersey and said he hoped the standoff would be resolved.

"It's a good thing that sport is more inclusive," he told reporters on Tuesday.

"It's important that in Australian society, we respect everyone for who they are."

The controversy has completely overshadowed the NRL's launch this week of its "Women in League Round," which is focused on the role of women in the sport and tackling gender inequality.

The boycott was criticized widely on social media, with the players branded "bigots" and "homophobic."

Hasler said the club needed to support them, particularly on the "mental health side."

"We'll do what is needed," he said.

Manly will now be shorthanded for a match that could have a significant impact on the team's chances of qualifying for the NRL playoffs.

The Sea Eagles are ninth on the table, on equal points with the eighth-placed Roosters with six rounds left in the regular season.

The top eight teams qualify for the playoffs.

"That's the situation we're in right now," Manly captain Daly Cherry-Evans told reporters.

"Unfortunately we're not going to make everyone happy. And like a lot of things in life, we can't make everyone happy."