Mauricio Pochettino accused his Tottenham players of throwing away the chance of their first Wembley win of the season.
Spurs were on course to end their Wembley jinx thanks to Dele Alli's strike, but Chris Wood grabbed a dramatic stoppage-time equaliser as Burnley snatched an unlikely 1-1 draw.
Tottenham's sorry record at their new temporary home now reads just one win from their last 11 matches.
But Pochettino insisted: "Wembley wasn't the problem. We played well. But still the team is showing a lack of concentration in different situations.
"I'm disappointed how we conceded the goal, disappointed because we showed a lack of concentration at the end.
"It was a difficult game, but in the end we knew we were capable of scoring, but you cannot show that lack of concentration at the end. That was our mistake. We need to take responsibility, it was our fault.
"Overall the performance was good, we created a lot of chances to kill the game. But we gave them the chance to score and for me that is tough to accept. When you have the three points in your hands you can't concede in that way."
