Following last night's 4-1 defeat against A-League leaders Sydney FC, the Phoenix had scraped to three draws, with seven losses to go with their solitary win.
They have been outscored 25 goals to 15 and are bottom of the table, four points behind ninth-placed Brisbane.
With just six points from their first 11 games, the Phoenix are battling to avoid the lowest points tally in their history — the 20 they totalled in their 2007-08 debut season, with only 21 games played in what was then an eight-team league.
Phoenix captain Andrew Durante said it was disappointing that the Vidosic pair had left Wellington but their departure has had an impact on the environment at the club.
"For me and other senior leadership players, we have a huge responsibility to make sure that it's a happy environment, that we all understand why these issues are happening and why we're not winning games.
"Especially in tumultuous times like this, it needs to be upbeat, it needs to be positive, as positive as you can be, and we have been."
While there was speculation that their exit was part of a campaign by the Phoenix board and Kalezic, general manager David Dome denied that was the case.
"They had a number of meetings where they tried to work out their differences and how they were going to proceed forward," he told Newshub. "It certainly wasn't part of an orchestrated campaign."
Despite winning just once this season, Dome insisted the club was not in crisis mode.
"We're going through a rebuilding effort. Darije has come in with a new level of professionalism," said Dome.
"We've made a lot of changes in the back room to meet his expectations and what he wants to change on the field. Those things don't happen overnight."
