Adelaide 36ers management has blamed Scott Ninnis' failure to meet club standards for the decision to fire the coach two weeks into the first pre-season of his new NBL contract.
Club management met with club legend Ninnis to terminate his contract on Monday morning, installing assistant coach Mike Wells to the top job for the season that begins next month.
The news came as a shock to the playing group and Ninnis, who only signed his two-year deal in February following a solid stint as interim coach.
Sixers chief executive Nic Barbato and general manager of basketball operations Matt Weston fronted the press on Monday afternoon to explain the decision, claiming Ninnis' short reign had been a "constant challenge".
"In those six months, we wanted to give every chance to succeed and it became clear to us that those standards weren't being met on a consistent basis," Barbato said.
"As an organisation we wanted to give every ability for Scott to improve, to learn to adapt and that didn't happen in our view.
"There's been challenges pretty much from day one of the six months. If we're honest with each other, there's been a constant challenge.
"We've decided it's better to make this call early. In the past we haven't done that, we've let that go when we have had doubts. We've made the call early to give ourselves the best chance to succeed this season."
A long-time NBA assistant coach, Wells' stint in charge began with practice on Monday.
Sixers management hired Wells as an assistant to Ninnis ahead of the current season and denied the ex-coach had felt undermined by that decision.
"I wouldn't think so," Weston said.
"He was a good resource to bring in to help Scott and I just don't think that's been activated the way I'd like."
Ninnis is set to be offered a job to remain with the Sixers in a community engagement capacity, given his long history at the club.
Originally coach between 2008 and 2010, Ninnis won eight of 15 games after taking over from embattled former boss CJ Bruton midway through last season.
The Sixers ultimately missed finals by one win and percentage, marking their sixth consecutive campaign without a post-season appearance.
Adelaide has burned through four different coaches in that time: Joey Wright, Conner Henry, Burton and now Ninnis.
As a player, Ninnis guided the 36ers to NBL titles during the 1986 and 1998 seasons, also playing for South East Melbourne Magic in their first title win in 1992.
Adelaide have signed former NBA big man Jarell Martin for the upcoming season, with Cairns Taipans forward Lat Mayen another key acquisition.
