Marcelo Bielsa insisted the better team lost after his Leeds side were beaten 1-0 at Charlton.
Macauley Bonne was credited with the game's only goal when the striker, making his first start in the Championship, was in the right place at the right time to deflect a punch by goalkeeper Kiko Casilla over the line in the 32nd minute.
Leeds ended up with 72 per cent of possession and had a total of 19 shots to Charlton's three but left London with nothing to show for their dominance.
The Yorkshire side, top of the Championship before Friday, dropped to fourth, level on points with newly-promoted Charlton.
Bielsa was adamant, however, that there was in fact a huge gulf between the two sides that the scoreline could not mask.
"The difference between the two sides was big," he said. "We didn't impose our superiority and that was the reason for what happened. They had one shot and scored one goal.
"We had possession and controlled the game. Our players were better than their players. We didn't underestimate our opponents but we had more resources on the pitch."
Bonne's goal came from a corner that Leeds allowed to reach centre-back Tom Lockyer, whose shot was parried on to the Charlton man and into the net.
Bielsa conceded that Leeds were too vulnerable from set-pieces.
"It's a fact that we are letting in too many goals from them," he said.
Charlton manager Lee Bowyer, who played for both teams in the 1990s, argued his players' hard work had made them worthy winners, especially as they had lost their previous two games.
He said: "To beat the best team in the league is always a good achievement. I thought we deserved it. We knew we were going to be under pressure at times because everyone who plays Leeds is.
"But we held our own and tactically got it spot on. I can't praise my players any more – they are a group that never says die. To get three points just shows how far we have come as a club.
"If you don't work hard for the team then you don't play, they all know that. They are a good, honest bunch who want to do well in this division. They are hungry."
The defeat was Leeds' first away from home in the Championship and the first since Bielsa won the FIFA Fair Play Award.
That was for allowing Aston Villa to walk the ball into their net following a controversial Leeds goal towards the end of last season.
The award raised a few eyebrows, not least in Derby, whose complaint to the English Football League that Bielsa had sent spies to their training camp earlier in the campaign resulted in Leeds being fined £200,000.
Chelsea boss Frank Lampard, who was Derby manager at the time, was critical of the award, but Bielsa said: "I understand him and respect him. If you have made one mistake and already been punished then sometimes your next good action can be recognised."