Jose Mourinho questioned the "attitude" of his Tottenham players and apologised to club supporters after Thursday's shock Europa League exit.
Spurs blew a 2-0 aggregate lead in Croatia as Dinamo Zagreb emerged 3-0 winners in the second leg of the last-16 tie at Maksimir Stadium.
Mislav Orsic scored a stunning hat-trick to complete the upset, with the last of his goals coming in extra time, and Mourinho bemoaned his team's lack of hunger to win the game after the final whistle.
"If I forget the last minutes of extra-time, where we did something to get a different result and go through, in the 90 minutes and first half of extra-time was one team that decided to leave everything on the pitch," Mourinho told BT Sport.
"They left to sweat, energy, blood. In the end, they left even tears of happiness. Very humble and committed. I have to praise them. On the other side, my team. I repeat, my team. They didn't look like it was playing an important match. If for any one of them it is not important, for me it is.
"For respect, I have for my career and my job, every match is important. For every Tottenham fan at home every match matters. Another attitude is needed. To say I feel sad is not enough.
"What I feel is much more than sadness. I just left Dinamo dressing room where I went to praise the guys and I feel sorry one team is not my team won the game based on attitude and compromise. I feel more than sad. That is it.
"Football is not just about players who think they have more quality than others. The basis of football is attitude. They beat us on that. I told the players the risk of playing the way we were. It happened because I believe the players only realised it was at risk when they scored the second."
Spurs have only got one trophy left to play for after being dumped out of the Europa League, and they are in real danger of missing out on a top-four Premier League finish.
Mourinho's side fell six points behind Chelsea, who currently occupy the final Champions League spot, following a 2-1 derby defeat to Arsenal at the weekend, which marked their ninth top-flight loss of the season.
Tottenham could have qualified for the continental competition by winning the Europa League, but they will now have to win the majority of their remaining ten games to have any hope of making the cut.
The Lilywhites will also be heavy underdogs when they take on Premier League leaders Manchester City in the Carabao Cup final in May, and Mourinho's position could come into question before then if results don't pick up immediately.
"I can only apologise to the Tottenham supporters," The Portuguese boss added on his team's latest setback. "I hope they feel the same way I feel.
"Today is live or die and at this moment we die. In some other matches, I have the same feeling. Until the last day of the season, we have to try and do our best."
Tottenham will now turn their attention to a must-win top-flight fixture away at Aston Villa on Sunday, with the international set to come into effect thereafter.