In a statement shared by the team on Twitter, Joshua explained that he was diagnosed with testicular cancer over the summer and had surgery to remove the tumor.
Fortunately, the surgery went well, but Joshua is still recovering.
"Unfortunately, I will not be ready for the start of training camp as I continue to heal from surgery," said Joshua in the statement. "I plan on returning to play as soon as possible this season and I am working hard every day to re-join my teammates."
He also emphasized the importance of seeing a doctor early and encouraged regular checks for testicular cancer.
"As I continue with my recovery, I thank everyone in advance for respecting my privacy concerning this matter," said Joshua. "I thank everyone for their support and understanding."