LONDON -- Mauricio Pochettino has admitted that Tottenham have come crashing back to earth "after a few weeks in the sky" with Wednesday's 3-2 defeat to West Ham in the Carabao Cup.
Spurs looked on course for a place in the quarterfinals after goals from Moussa Sissoko and Dele Alli gave them a commanding 2-0 lead at half-time but they collapsed in the second-half, losing after Andrew Ayew's quick-fire double and a Angelo Ogbonna's headed winner.
Pochettino said his players allowed West Ham back into the back with a lack of aggression after the break and he took responsibility for the defeat, that followed the encouraging draw at Real Madrid and Sunday's 4-1 win over Liverpool.
"I think it's easy to explain. We showed a lack of aggression, all that we had in the first half, that belief and everything that we were doing very well, [we lost] in the second half," Pochettino said at Wembley.
"But that happens in football. We are so disappointed. The players are so disappointed and we are feeling for the fans. That is football.
"I think that we allowed them to come back into the game. In the first half it was under control and we played well and were 2-0 up. No, we are so disappointed and it was so difficult to explain in the second half to concede three goals in 15 minutes. We lost that aggression from the first half."
The Spurs manager, who made seven changes from the win against Liverpool, continued: "In football sometimes after a few weeks when we were in the sky because our performances against Real Madrid and Liverpool were fantastic I understand sometimes. Today it's not easy to play this type of competition and when you rotate, rest some players, sometimes it's so difficult.
"It's difficult to keep the momentum and try to perform in the same way. That is of course my responsibility always. Of course I am so disappointed but we need to rotate. We need to use all the players and give all the players the possibility to play. Always it's my decision and of course my responsibility."
West Ham boss Slaven Bilic believes his side's thrilling fightback can breathe life into their faltering season.
"It can give us a lot of confidence, but only to do the same in training, to do the same on Friday, on Saturday," said Hammers boss Bilic.
"We have to use this opportunity to work hard. We have two days before Palace, it's not ideal but the win gives you energy, gives you freshness.
"Now tomorrow at the training ground nobody is going to feel tired, from the impact of our result, from beating them."
Information from PA Sport was used in this report.