Manchester United loanee Amad has confirmed he has played his last game for Sunderland.
The Black Cats were beaten in the play-off semi final second leg against Luton Town on Tuesday.
With their season at an end, Amad is heading back to United, where he will hope to play next term.
Diallo commented on an Instagram post from a Sunderland fan page, which was bidding him farewell.
Amad wrote: "I have loved every moment here in Sunderland, I wish you well and will support you for the rest of my life...thanks."
He then posted again: "Hi guys, i know you are sad, we all are. a group of young guys who fought until the last minute, I can only be proud to have been part of this team.
"No regrets just proud of what each of us has become over the course of the season. thank you for the love. HAWAY THE LADS."