Mauricio Pochettino conceded Tottenham's title hopes are all but over after losing 2-1 to Burnley at Turf Moor.
Harry Kane scored on his return from injury after six weeks out but goals from Chris Wood and Ashley Barnes sealed an impressive win for the Clarets.
The defeat leaves Tottenham five points off league leaders Manchester City and Liverpool, who have a game in hand, with just 11 games left to play.
And Pochettino, who became embroiled in a heated discussion with referee Mike Dean after the final whistle, was frustrated with his side's inability to secure the three points.
"I think it's important to understand that it was an important game and it was going to be decisive," he told Sky Sports. "I believe that if you want to be a contender you need three points.
"We made a few mistakes and conceded two goals. Congratulations to Burnley. They fought a lot and had a good game. We didn't deserve the defeat but this is football and we must keep going.
"For me, we're really disappointed. There are only 11 games left, the gap can be bigger and [there are] games to play, but today, I think in my mind to win the three points, to put pressure on them [Liverpool and Man City]... we didn't. We cannot blame anyone but ourselves because we were not able to win."
Pochettino could face action from the Football Association after angrily remonstrating with Dean on the pitch about the decision to award a corner for the first goal, with several members of the Spurs coaching staff also becoming involved in the incident.
The Argentine revealed he would accept an FA charge but hoped that context of the incident would allow him to escape punishment, explaining that emotions were running high for his side.
"The emotions, everyone was nervous, sometimes we have answers or excuses, it's not normally how I behave," he added. "I knew very well before and after the game, it was going to be difficult.
"I will accept everything that can happen from the FA but I think some things that happen on the pitch happen on the pitch. I don't know. Hopefully it is not going further."
