Joseph was shipped to Indiana on July 14 as part of a sign-and-trade for C.J. Miles, along with the draft rights to forward Emir Preldzic.
The 25-year-old called playing for his hometown team “a privilege,” and that he was looking forward to meeting the fans in Indiana.
“It was an honour to play for you and rep The Six!” he wrote. “Toronto will always have a place in my heart.”