Andrew Clark has joined up with Graham Arnold once again after being appointed Sydney FC's head of strength and conditioning.
Arnold has previously worked with Clark at Central Coast Mariners and Vegalta Sendai, and said he was pleased to be teaming up with the former Mariners defender again.
"I've had a great working relationship with Andrew Clark during our time together over the last four years," said Arnold.
"He excels at what he does in getting players fit and healthy and keeping them that way. He is a great addition to the club."
Clark, who will begin work with immediate effect, said he was looking forward to working with Sydney FC.
"Sydney FC is a club with a great history, having won two Championships and played Asian Champions League football," said Clark.
"I'm extremely humbled and thankful to have been given the opportunity to be part of a great future for the club.
"My goal is to give every player the chance to perform to the best of their ability and I'm proud to be part of the ambitious plans going forward."