Bleiberg is now required to explain by Wednesday why he shouldn't be sanctioned for questioning the integrity of referee Peter Green after United's controversial 3-2 loss to Sydney FC at the SFS.

The United coach labelled Green a 'homey' - an official who favours home sides in 50-50 decisions - and said that Karol Kisel's last minute winning penalty would not have been given at the other end.

The club has since issued a statement in which Bleiberg apologised for his remarks, saying they were made 'in the heat of the moment'.

Speaking upon arrival back on the Gold Coast this morning, Bleiberg stood by his comments but rued his own poor choice of words.

"I didn't say I regret what I said, you read my apology. I should have said it differently, simple as that," he said.

"I didn't say that I didn't mean what I said, I wasn't drunk. I just should have put it differently, in a nicer manner.

"I said what I said because I felt what I felt, I had 24 hours to think about it, and then I gave an apology that said why I said what I said. It was 50 per cent emotion, 50 per cent brain."

United were good value for their 2-0 lead in the second half but Bleiberg said a series of events - including a corked thigh to Ivorian left-back Adama Traore and the injury-time penalty - conspired against them.

"Straight after the second goal we had to replace Adama - that's what turned the tide," he said.

"Once we have to change the first XI to a different structure, and you play against a home team, like Sydney, it's a psychological game - nothing to do with ability or tactics.

"One team is on the ropes and the other has their back to the wall. What happened, happened and if you're not helped by (referee) decisions then you feel even more miserable."

Fortunately for United, Traore is expected to recover from the injury in time to face Adelaide United at Hindmarsh Stadium on Friday night.

That's welcome news for Bleiberg, who was critical of the performance of the Ivorian's replacement, Ambes Yosief in his post-match interview.

One of two Eritrean refugees signed by the club from the South Australian Super League, Yosief had a torrid time out of position at left-back with Sydney superstar Brett Emerton giving him hell on the right flank.

Bleiberg added: "Under the limitations, he was our best option and he tried his best like anyone would, but it was a lack of experience.

"The guy had 30 minutes in the A-League (prior to Sunday),"