The 35-year-old former professional football player Jergé Hoefdraad, who was shot in a business building in Amsterdam on Sunday morning, has died in hospital, the police reported on Monday.
He was believed to have been shot during a party.
Hoefdraad may have tried to calm a fight between people at the party.
A police spokesperson previously said that that scenario is "very plausible".
The detectives are now investigating that scenario further.
Hoefdraad was only active in the Netherlands as a football player.
He started in the youth at Ajax and then played successively for RKC Waalwijk, Almere City (and its predecessor FC Omniworld) and Telstar in the Eerste Divisie.
Hoefdraad played in the Eredivisie on behalf of Cambuur in the 2015/2016 season.
From next season, the attacker would play at the Amsterdam amateur club ASC De Volewijckers.
The club's board responded to the incident via its website.
"Today we received the sad news that Jergé Hoefdraad was shot and taken to hospital in critical condition. Jergé, we are thinking of you. A lot of strength to family, friends and teammates in this time."
Police are still looking for witnesses with more information about the incident at the party. They are also looking for videos, photos and selfies from earlier at the party and during the incident. These images can be sent anonymously via Meld Misdaad Anoniem.