Northland rugby league player Mike Salase has died while playing the game on Saturday.

Police said they were notified at 3.40pm yesterday that a person had suffered a medical event while playing league in Broadwood, Northland.

"CPR was undertaken at the scene but sadly the person was unable to be revived," a police spokeswoman said.

Players formed a barrier to give Salase privacy as emergency services worked to revive him.

Northern Swords Rugby Club said it was with "deep regret and profound sadness" when it posted about Salase's passing while "playing the game that he loved".

"Like many of our rugby league whānau in Northland we are extremely shocked by this news and our sincere condolences go out to Mike's whānau and friends at this time," the post said.

"Our thoughts and prayers also go out to Hikurangi Stags and Pawarenga Broncos whanaunga who were with him during his final moments."

The club described Salase as a league stalwart in Northland and a member of multiple Northern Swords senior men's teams including the 2020 team who won the National Championship last year.

"All of us here at Rugby League Northland and Northern Swords, we will miss that cheeky smile of yours brother," the club added.

Tributes and messages of condolences have been pouring in from friends and family.

Salase's mother, Denise Salase, wrote: "I will miss my boy forever, I can't believe you have gone but in my heart I know you are with your dad and that is the only thing that gives me peace.

"I love you my son, I miss you my heart."

His was the son of Vili Salase, also a known league player in his time.

Teejay Williams said Salase was an amazing player who will be missed.

"A man I'll never run straight into. His shoulders were built to knock guys out," Williams wrote.

Caleb Tana said they started playing seniors the same year, and Salase was a lovely person off the field too.

The Hikurangi Stags described Salase as a "true legend of the game and a legend of a man".

"Michael [was] quiet and humble in nature and was the most feared defender in Northland rugby league over the last 15-20 years, and also an excellent runner with the ball in hand," it said.

Salase played a majority of his football for Portland Panthers, according to the Stags, while also spending time at Otangarei Knights, Horahora Broncos and the Hikurangi Stags.

The Pawarenga Broncos gave a "big mihi" to those who worked tirelessly trying to revive him and those who formed a barrier to provide privacy for him during the incident.

"This is something you never believe will happen and we are left feeling very deeply for all concerned in the great sportsman's passing," it said.