Croker underwent revolutionary stem-cell surgery on his knee this off-season in a bid to save his rugby league career.
The 31-year-old centre barely missed a game in his first 12 NRL seasons but the past 18 months have been plagued by injuries.
A shoulder reconstruction after the 2020 season was followed by debilitating knee pain which led to several minor surgeries on his meniscus, and platelet-rich plasma injections.
But those solutions proved temporary and Croker went under the knife last October in a bid to fend off medical retirement.