It will be Gustafsson's first bout in over a year. He defeated Glover Teixeira at UFC Fight Night 109 in May 2017. Oezdemir, meanwhile, lost to Daniel Cormier at UFC 220 in January.
Okamoto added UFC will have to alter its original plan for UFC Fight Night 134 on July 22. Oezdemir was set for a main event fight with Mauricio Rua, so Rua will now need a new opponent in Hamburg, Germany.
The implications of Gustafsson vs. Oezdemir could be big for UFC's light heavyweight division. The two fighters are the No. 1 and 2 challengers, respectively, behind light heavyweight champion Cormier.
Given his lengthy layoff, having Gustafsson come back and immediately fight for the title wouldn't have made much sense. Plus, Cormier is moving up to the heavyweight division for a highly anticipated bout with Stipe Miocic at UFC 226 on Saturday.
Should Gustafsson beat Oezdemir, especially in a decisive manner, he'd be in position for a shot at Cormier.
The situation would become a little more murky if Oezdemir prevailed, since Cormier won via second-round TKO during their January meeting. UFC may have reservations about a rematch so soon after UFC 220.