Mauricio Pochettino tore into his Tottenham Hotspur players after watching them surrender the lead and an early position of strength to lose 2-1 against Anderlecht in the Europa League, and accused them of losing focus.

Tottenham started the match well when Christian Eriksen scored in the fourth minute and the team created several other clear chances in a 10-minute burst at the outset. But they switched off to concede a dreadful equaliser to the Anderlecht full-back Guillaume Gillet from a set piece and, thereafter, allowed the tie to slide away from them.

Stefano Okaka, the one-cap Italy striker and one-time Fulham loanee, scored the winner and it came as no surprise, particularly to Pochettino who was furious.

“Angry, frustrated, disappointed – I don’t know which is the best word to describe me,” Pochettino said. “We need to realise that we need to compete in every game, in every single minute, in each different game, in each different competition.

“It’s difficult to say, ‘OK, 1-0 up, now I don’t put the effort in, I lose my focus.’ We need to be focused for 90 minutes, 95 minutes. If not, football is like this. The dynamics change quickly.

“We started very well. After 10 minutes, we are 1-0 up and we create two, three chances more. But when you concede the possibility to the opponent to come back into the game the way that we conceded here, the dynamic changes.

“It is not normal that we concede the chance that we concede. We lost our focus on the game and, after 10 minutes, the game changes completely. We need to learn. We are very young but we need to learn a lot. When you are the best team on the pitch after 10 minutes and you believe that you can win the game, you need to win the game. Your focus needs to be 200%. But when you lose your focus, it is difficult to come back.”

Tottenham are now third in Group J and Pochettino described the return tie against Anderlecht at White Hart Lane in two weeks’ time as “must win”. He added: “We’re under pressure but I am happy about that. We need to feel the pressure because here, we didn’t feel the pressure after 10 minutes and it seemed it was an easy game. Then 2-1 and we lose.”