The Mariners announced on Friday Moss had been “stood aside” and is now in negotiations with him around his position.
The cash-strapped Mariners have struggled on the field this season and sit eighth in the 10-team competition - eight points outside the top six - with just three wins from 19 matches.
Walmsley will fill the head coach’s position in an interim capacity.
“The decision is part of stage two of Mariners Executive Vice Chairman Peter Storrie’s restructure that will also see Hyundai A-League Assistant Coach Wayne O’Sullivan offered a new role at the club,” a club statement read.
The move is also a boost for club legend John Hutchinson, who will step into a player/coach role until the end of his final campaign as a player.
“The specifics of Hutchinson’s coaching contract are yet to be finalised but fans, media and members can be rest assured that the club captain will remain with the Mariners in a coaching capacity beyond this season,” the statement continued.
“The next phase of the Central Coast Mariners restructure will also include a fresh look at the operation of youth football that will be made evident in the near future with further statements.”
Experienced English club administrator Storrie was brought into the club by owner Mike Charlesworth at the start of the year with a mandate to review the Mariners' structures and also lead a marketing and commercial campaign to boost revenue.
The club said it would soon commence the search for a new permanent head coach, with Walmsley to remain as the club's technical director.
No further statements on the circumstances behind Moss’s sacking were available from the club.
