Speaking on the TOMorrow Business Podcast, Wirth explained: "Looking back, we have to say the transfer didn’t work out. There’s no point in sugar-coating it."
“This always has to happen in cooperation with the club, but I believe it can make sense to change something there."
“Time and again, at a point where you said, 'Now he’s coming, now he’ll show England that it wasn’t just a good European Championship and then nothing more will come of it,’ another injury came along, and that’s a shame,” he continued.
Fullkrug is currently sidelined with a thigh injury and missed [West Ham](/topic/west-ham)’s 3-1 victory over Newcastle on Sunday.
The veteran hitman had found favour under [Nuno Espirito Santo](/topic/nuno-espirito-santo), starting the West Ham head coach’s first two games in charge.
However, his injury issues have meant Nuno has been unable to rely on him with West Ham in desperate need of goals.
Fullkrug fills a hole for West Ham, who lack a focal point in attack, but with the Hammers facing up to a relegation battle and Fullkrug keen to make an impression on Germany manager Julian Nagelsmann, his departure from the club appears likely.