Dejan Kulusevski has acknowledged Tottenham must improve their mentality and learn from Arsenal if they are to compete with them next season.

Fifth-placed Spurs suffered a painful 3-2 defeat at home to their north London rivals on Sunday, but were staring down the barrel when three goals behind at the break.

Ange Postecoglou’s team produced a stirring second-half rally and yet with their faint top-four prospects nearly over, Kulusevski admitted they must become more consistent.

“That is the only thing that matters – the head,” the Swedish attacker insisted.

“You can be how good you want in football but you’ve got to be strong in every situation.

“Arsenal have obviously done that in the last period. They fight to win the league. We still have to do that. We are improving in other areas, but we still lack a little bit in that part.

“I don’t think it is about ambition. I think everybody wants to win but then you have to sacrifice a lot for that.

“Talking about mentality, do you think it is easy to be down 3-0 at half-time and then go out and play 3-2 against the ones that are first? That is also mentality.

“Second half was unbelievable. It is just that you have to show it for 90 minutes. If not, it is difficult. We are showing it in bits but we have to do it much more consistently.”

One of Tottenham’s best performers on Sunday was Kulusevski but it failed to prevent a third defeat from their last six matches as Postecoglou’s fine debut campaign threatens to end with a whimper.

While the Spurs attacker does not believe the gap to Arsenal is too big, he accepted the Gunners’ discipline and set-piece prowess demonstrate areas where his side must improve.

Kulusevski added: “It is always the bigger picture in sport but then we have to take responsibility.

“We have to win games. We have to improve. If we are not doing that then people are of course going to be disappointed.

“We have to grow because you cannot concede easy goals like that. The football is quite good, but we have to improve (mentally).

“They (Arsenal) are much more disciplined and a little bit more mature. That is where we are lacking at the moment.

“Being strong in difficult moments like a set-piece. Things like that. They score on corners, we concede. It is quite easy.”

Micky van de Ven also impressed for Spurs, but expressed his frustration at conceding from two corners.

Spurs have shipped 14 set-piece goals – excluding penalties – this season, which is the sixth-worst record in the division.

“Two goals from set-pieces of course is frustrating. We have to train hard and to work on it this week,” Van de Ven said.

“I don’t think in the football part we are worse than Arsenal. The mentality from them is strong but I wouldn’t say that either.

“You see their goals and they were ruthless. They took every chance and I think that makes the difference.

“The first half was not good from us, 3-0, it can’t happen in your own stadium in a big game like this. You cannot concede three goals at home if you want to be a top team and we have to work on it.”