Marco Kurz conceded it was just one of those days as Adelaide United were beaten 5-0 by Melbourne City at AAMI Park on Sunday night.
Marcin Budzinski and Dario Vidosic both netted braces before Ross McCormack sealed the three points for the hosts in style.
Kurz admitted it was the worst performance of the season, but stressed it is just an anomaly.
He said his side’s high-pressing game contributed to his team’s downfall in the first-half.
“It’s the first and one of our worst games this season,” he told reporters in the post-match press conference.
“If you see the first chance after nine minutes from AP (Apostolos Stamatelopoulos) he runs alone to the goalkeeper and can score the first goal.
“But sometimes you don’t have the quality today to score goals, you don’t have the quality to make a good pressing.
“I think in the first-half we didn’t press well, we opened the whole space for Melbourne City and they played well in this situation.
“But it’s football and you have such off days like today and I think it’s important to analyse this game and then look forward.
“For us it’s a very bad night, a very bad game but it’s also only one game.”
Despite the one-sided scoreline, Adelaide had two great opportunities – first at 0-0 and then midway during the second stanza while trailing 2-0.
Kurz intimated the result somewhat flattered City.
“I think the biggest chances today in the game were on our side,” he said.
“From AP and (George) Blackwood and that’s maybe typical for this type of game we have the two biggest chances and we scored no goals.
“And they scored beautiful goals from thirty metres or thirty-five metres, but in this moment I’m sure if we made it 2-1 we have a chance, but today was not our day.”
The Reds remain in fifth place on the Hyundai A-League table, three points clear of the sixth-placed Western Sydney Wanderers.
Adelaide United will face Wellington Phoenix in Round 18 of the Hyundai A-League 2017/18 season on Saturday, 27 January at Westpac Stadium. Kick-off is at 5.05pm ACDT.