Tottenham coach Mauricio Pochettino conceded his side did not show enough intensity or aggression as they slipped to a 1-0 Premier League home defeat to Aston Villa on Saturday.
Christian Benteke's first-half header was enough to see Villa boss Tim Sherwood record a win on his return to White Hart Lane having been sacked as Spurs boss last summer.
The defeat to relegation battlers Villa -- coupled with Sunday's draw at Burnely -- have left Spurs' top four hopes hanging by a thread, and Pochettino feels Sherwood's side showed greater determination to earn the points.
"From the beginning of the game we made it difficult for ourselves because we didn't manage the ball properly," he told the club's official website.
"We gave them easy possession and then we conceded the first goal with the first chance they had. After that we tried but it's always difficult when you go 1-0 down.
"Maybe there was a lack of intensity in the first half, we increased that in the second half but it wasn't enough. When you play a team like Aston Villa or Burnley, they play for survival, they increase their levels and are more aggressive.
"You need to match that aggression and maybe we were one step behind. In the last two games it's been difficult for us, we haven't scored and we need to push hard and to increase our performance."