William Hill purchased a 92% stake in Mr Green’s parent company, MRG, in a £245m ($315m) deal in January.
Jonker is yet to begin in his role at William Hill; he is due to start in mid-March, having served as Managing Director of operator Betsson Group since 2014.
This means Per Norman will step down from the position as CEO of MRG, and Kärrbrink will leave the role of CEO of Mr Green Ltd – the Malta business.
Norman will move into an advisory role as Chairman of GLHF, a yet-to-launch venture focused on building an esports community, owned by MRG. Norman has been MRG CEO since 2015.
Kärrbrink will move to Sweden to take up a new role with supplier Green Jade Games, also owned by MRG.
Gambling Insider understands all changes in management were always planned as part of the acquisition; the offer was first announced by William Hill in October. Kärrbrink has been with the operator since April 2016, and is understood to have always planned to be based in Malta for no more than three years after taking up the role.
Mr Green is not said to be searching for a CEO of overall operations, with Jonker set to be the phead for all Mr Green’s performance, and all aspects of the business now operating under one umbrella.
On taking up the new position, Jonker said: “Mr Green is a successful business and I am looking forward to working with the team to maximise the growth potential of our leading brands and products.”
Kärrbrink said: “The past three years has been a fantastic journey with some of the most amazing people in the industry. I have planned to move back to Sweden for some time, so it is reassuring to know that the existing management team lead by Patrick Jonker as Mr Green Ltd’s new CEO will take the company forward to the next stage of the journey as part of William Hill. I look forward to continuing working closely with William Hill through Green Jade Games.”
Norman said: “The strategic and logic of the acquisition is obvious, strong brands and size are prerequisites for future success. I am excited to be engaged and follow the William Hill group through my board position in GLHF.”
William Hill said adding Mr Green to its business will increase its digital revenue base from 24% to 35% pro forma.
Shares in William Hill dropped to 172.5 GBX from a high of 178.45 GBX on Tuesday.