Markus Babbel claims A-League referees are biased against his team, a day after the Western Sydney coach was reprimanded by Football Federation Australia for a previous blast at match officials.
Babbel was at it again after Saturday's 2-1 loss to Wellington in Auckland, the Wanderers' fourth defeat in succession, three of which have been overshadowed by contentious referee decisions.
Former Germany international Babbel could be back in hot water, along with Wanderers defender Daniel Georgievski, who on Friday was handed the same FFA formal reprimand as his coach for a breach of the national code of conduct after last month's 3-2 loss to Melbourne City.
Georgievski was shown a yellow card at Eden Park on Saturday for persistently remonstrating with match officials, after referee Daniel Elder awarded a marginal late penalty for handball.
The match-winning spot kick was converted by Wellington's Ulises Davila, prompting fury from the visiting players and a post-match conspiracy theory from Babbel.
While he didn't unleash the expletives that followed the City loss, he told the media it could no longer be regarded as unfortunate that key decisions go against his team.
"You can't tell me this is bad luck," Babbel said. "This is too often now, too often against us, and there's something behind it, that's my opinion.
"We have to understand that we play not against 11 but against 12 -- this is a trend now.
"I really feel sad for the boys but it is like it is and we have to work harder."
Pirmin Schwegler has been at the centre of the two most disputed rulings against Western Sydney.
The Swiss midfielder made gentle contact with Denis Genreau which resulted in the penalty against City that sparked Babbel's ire and prompted Georgievski to post an inflammatory picture on social media.
On Saturday, Schwegler arm was struck at close range by Davila's blast at goal.
He didn't have time to react but a penalty was awarded on review of a VAR monitor by Elder because the arm was away from the body.
Babbel pointed out his team warranted an earlier penalty themselves for handball by Phoenix captain Steven Taylor.
"Why can't we get a penalty but the opposite side get one? There is frustration there," he said.
"I think I have to apologise to my players, because three weeks ago I said something publicly, and once it happens, twice, but now three times in a row, then it's I think a bit personally against me."
Wellington have benefited from four penalties this year, all converted by Davila.
Coach Ufuk Talay agreed with Elder's ruling.
"The rules are, if it hits your hand and your hand's away from the body, it's the referee's call to make a decision," he said.
"As long as there's consistency in the decisions that they make then that's what it's [VAR] there for."
Wellington's third-straight win lifted them up to fourth, level with Western Sydney on 10 points.