Dele Alli says Tottenham need to learn from their mistakes in last night’s Champions League defeat to Monaco, starting games quicker and being more clinical.

Heung-Min Son had an early shot cleared off the line at a packed-out Wembley Stadium, before two defensive lapses allowed the visitors to go 2-0 up just after the half-hour mark.

Toby Alderweireld halved the deficit before the break and Spurs were on the front foot for most of the second half, but they could not find an equaliser, with Harry Kane squandering the best chance when he shot straight at the goalkeeper from the centre of the penalty box.

“The fans showed great support with the numbers coming out,” said Alli. “We need to make sure we learn from our mistakes and start games quicker and brighter. We need to finish strongly as well and be a lot more clinical.

“It was never going to be an easy game for us. We know how good they are from last year when we played against them [ in the Europa League].

“They’ve improved but they weren’t easy last year. We didn’t help ourselves in the first half. In the second half we dominated it but we weren’t clinical enough. I think we did enough to win the game but unfortunately it wasn’t our night.

“We’re definitely a confident side and we do expect to win games, no matter who is in front of us. We’ve let ourselves down in that first half when we should have been better.

“We usually bounce back quite well from a defeat and we’ve got the next game against Sunderland [on Sunday] and the game after that, so it’s important that we do pick ourselves up and learn from it and make sure we improve and take that into the next game.”

Asked if Spurs found it difficult to find the right balance between attack and defence on their return to the Champions League, Alli said: “It’s not that hard. It’s something we’ve worked on during the week because we know they’re a counter-attacking side.

“We knew that from the start. It’s just ourselves. We knew what to expect, we had tactics, I just think the slow start killed us.”

Alli was initially deployed in a deep-lying midfield role alongside Eric Dier but pushed forward to aid Spurs’ offensive endeavours – and he was then moved into the No10 role at half-time as Mousa Dembele emerged off the bench, making his first appearance of the season after completing a suspension.

“I’m happy to play anywhere in this team,” said Alli. “It’s just a privilege to be a part of the team and to be out there playing. When I was at MK Dons I played all the games in centre midfield so it’s not like it’s new to me.

“Mousa’s a fantastic player, there’s no doubt about that. He’s a brilliant player and we’re excited to have him back - but Victor [Wanama] has done really well since he’s come in, and Eric as well in centre midfield.

“With the amount of games we’ve got coming up it’s important to have a lot of depth in the squad and it’s good that Mousa can come back and fight for his place in the team.

“That’s what’s important when you’re in the Champions League, with the amount of games we’ve got. You need to have a big squad and keep working and keep going on the training field to get in that starting 11.”

Spurs were in fairly unfamiliar surroundings for their home game against Monaco last night.

They were cheered on by a bigger crowd than ever before – the attendance of 85,011 was a club record for Tottenham and, indeed, the largest ever home crowd for an English club.

However, the Lilywhites were playing on a bigger pitch than they are used to at White Hart Lane, and they now lost their last five successive games at the new Wembley.

That will need to change, both in the short-term as they bid to qualify from their Champions League group and also in the longer-term - Spurs are due to play all of their home games in every competition at Wembley next season, during their year away from Tottenham High Road.

“We’re a fit side, we do a lot of fitness work for occasions like this and we’re ready for it, so I wouldn’t say [the size of the pitch] played a big part in it,” said Alli.

“It’s a fantastic occasion for us, with all the fans, and you have to give a lot of credit to the fans who showed up and filled it, and they kept singing. Hopefully we’ll keep playing here and we’ll get a win.

“Obviously there are a few of us who have been here a few times before. We knew what to expect and even the players who played against England here, they knew what to expect. I suppose it will start to feel like home soon.”

Follow me on Twitter @BenPearceSpurs