LONDON -- Eric Dier says Mauricio Pochettino's Tottenham can be even better than Borussia Dortmund after the Germans ended Spurs' Europa League hopes.
A much-changed Spurs were thoroughly outclassed by Dortmund in the round-of-16, with the Bundesliga club winning 3-0 in Germany and 2-1 in Thursday's second leg to ease into the quarterfinals, where they will face Liverpool and former boss Jurgen Klopp.
Under Klopp, Dortmund won two Bundesliga titles and reached the Champions League final, and there are similarities between his Dortmund side and Pochettino's Spurs.
After seven years at Westfalenstadion, Klopp was replaced in the summer by Thomas Tuchel, who has maintained his predecessor's commitment to attacking football and high-octane pressing -- not dissimilar to Spurs' style under Pochettino.
Dier believes Dortmund -- who, like Spurs, are second in the league -- belong in the Champions League but believes Tottenham are on track to reach their level.
"I didn't play them in the first leg but from this leg I think they're probably the best side we've faced this season. They're a very good team but at the same time I think we could have done better in both legs," Dier told reporters on Friday.
"They play quite a similar style to us. I don't think they beat us with tactics or anything -- at times we should have been a lot better. But they're a team that's been progressing since Klopp was there. They've had I don't know how many years -- five or six -- to get to this stage. We're a year in with our manager and this group of players so if you talk to me in four years' time we'll probably be at their level or ahead of them. That's the aim."
The England midfielder echoed his manager and teammate Dele Alli by insisting Spurs must learn from the chastening experience of facing Tuchel's side, adding: "We can't look at it positively -- I don't think you can ever look at a loss positively -- but we have to learn from it and we should learn from it.
"If we don't then that will be a mistake. It was really good to come up against a side like that. They're a Champions League side really so to come up against them shows how far we've come from the beginning of last season and these are games we want to be winning and games we want to be fighting in so there's obviously still a lot to improve on.
"That's what we play football for -- to be challenging in every match and playing against the best teams in the world. Those are the teams you want to be playing against and challenging against. It was nice to play against one of them today and I'm looking forward to playing against more of them."
Thursday's match was Dier's 43th start of the season and he has played more minutes than any other Spurs player this term.
The 22-year-old insists he is not feeling fatigued, however.
"I'm not tired, I'm enjoying it! I don't think there's any excuse to be tired. All I do is play football every day. I'm not doing anything else so there's no reason for me to be tired. I'm enjoying every minute of it. You only play football for 10 years -- there's no point being tired for some of that.
"We're all young and we're all competitive and we work extremely hard on the training pitch to be as fit as possible and to prove it every weekend."
Spurs' sole focus is now their maiden Premier League title challenge but Dier is not convinced their European exit will aid Tottenaham's chances of overhauling Leicester, who lead by five points, in the final eight matches.
"I'm not sure to be honest -- it could help us, it could hinder us. Me personally, I quite enjoy playing midweek games," Dier said. "You get into a nice rhythm of non-stop matches and you get into a rhythm, which is quite nice, but at the same time obviously we'll have a couple of extra days' rest and we've got five or six-day weeks where we can rest, recover and then work on stuff on the training pitch, which we haven't been able to do since probably before Christmas."
Dier went on: "I don't know what anyone else has said but I think everyone's said the same thing all the way through. We're going game by game, we're enjoying ourselves, fighting at the top. It's nice to be in this position, this is what we play football for. We've got a very ambitious young team and an ambitious manager and we're going to fight in every game and see where we end up at the end."