"Liverpool had a lot of injuries but they put out a side like that," he said. "That's the difference between the top four clubs - and we know who they are: Chelsea, Manchester United, Arsenal and Liverpool - and the rest of the Premiership. Someone might come along to upset it. It might be Everton this year. But the top four clubs are the top four clubs."
Although Charlton began this match only a matter of goal difference below Liverpool in seventh place, they finished it, effectively, in another division.
Despite falling a goal down to a 20th-minute header from Shaun Bartlett following a corner by the Anfield old boy Danny Murphy, the visitors claimed the points thanks to a 61st-minute equaliser from Fernando Morientes - his first goal since last month's £6.3m move from Real Madrid - and an equally opportunistic effort 11 minutes from time by John Arne Riise.
Liverpool might have had more, too, had their captain, Steven Gerrard, not driven a rebound against the bar after Dean Kiely had beaten out Luis Garcia's initial shot. Indeed, Morientes would have got off the mark in the first half had Kiely not produced another inspired block from his point-blank shot after Riise had run amok down the left.
It was all very dispiriting for the majority of a 27,102 sell-out crowd, the highest at The Valley in 27 years.
After three defeats in their last four Premiership matches, the Carling Cup finalists knew they had no room for manoeuvre against a team who had beaten their fourth-placed neighbours, Everton, 10 days earlier.
"Liverpool came into the game knowing they had to win it," Curbishley said. "And I think it showed in the determination with which they played. I've got no complaints - on this performance they looked a class outfit."
And Morientes finally emerged as the classy striker everyone knew him to be. Liverpool's manager Rafael Benitez said he had spoken to his Spanish compatriot before the game about his growing impatience.
"For Fernando it was very, very important," Benitez said. "It was time for him to score. He was playing very well, and winning the ball in the air, but when you are a centre-forward and [one of] the top scorers in the Champions' League you need to score always.'
The Morientes moment arrived just after the hour, when Bryan Hughes lost the ball to Garcia in his own half and the ball was swiftly transferred to the newest Anfield arrival, who evaded a challenge before driving home a left-footed shot from the edge of the box to delight the travelling fans behind the goal.
The Liverpool supporters' joy doubled when their irrepressible ginger-haired Norwegian, Riise, won the race for Garcia's prodded pass to sweep home an angled shot from the left.
Curbishley had acknowledged on the eve of this match that February loomed as a critical month for his side's ambitions, given fixtures against their close rivals Newcastle United and Middlesbrough, not to mention an FA Cup fifth-round tie against Leicester City. His side made a huge effort, and might have earned a point if the referee Neil Barry had looked more kindly upon a reasonable penalty claim for handball against Igor Biscan in the second minute of added time. But they would not have deserved it.
As for Liverpool, Benitez is looking forward to continuing the building job around his towering captain, Gerrard. And their confidence appears to have been restored.