Tottenham defender Toby Alderweireld knows how important it is to have a marksman like Harry Kane in their side.

Kane became the club's leading European goalscorer when he scored in the second half to hand Spurs a 1-0 Champions League win at Borussia Dortmund, sealing a 4-0 aggregate success.

Dortmund would probably have gone through had they someone like Kane in their ranks as over the two legs they failed to take their chances.

Coming into the second leg at the Signal Iduna Park 3-0 down from the first leg at Wembley three weeks ago, they threw everything at Spurs in the opening 45 minutes, but could not make the most of their opportunities.

Kane needed only one chance after the break as he fired home clinically in the 49th minute.

"That's his quality," Alderweireld, who was part of the defence that stopped Dortmund scoring at home for just the second time this season.

"We know this. He does a lot of hard work for us as well.

"The team works hard and if he has a chance, especially in big European nights, we need him to score those goals.

"We knew if we scored a goal, they would have to score five. So we knew that it was over."

It would have been some capitulation had Spurs not got the job done, but it might have been different had Dortmund taken one of their early chances.

After seeing off a barrage of pressure in the first 35 minutes, Spurs were then in control and Alderweireld says they have matured from the side that were beaten by Juventus at this stage last season.

"It was very tough the first half an hour," the Belgian added. "But the team is growing, becoming much more mature to get through those kinds of moments.

"Of course, you need a bit of luck, a good goalkeeper but we dug in and we knew we wouldn't concede.

"And that's very important. Maybe the team of a couple of years ago, would concede and then it's much more difficult. We're making steps forward here.

"We're trying. The last game against Arsenal as well we worked hard, we dug in, concede and tried to get a good result. And again tonight.

"These big European nights are important to take the next steps. Like today. This is a very different ground to come to."

Spurs go to Southampton, Alderweireld's former club, in the Premier League on Saturday, but they will not have boss Mauricio Pochettino on the sideline as he has been handed a two-match touchline ban following his Football Association charge for improper conduct after the match at Burnley.

"We have a clear idea of how we want to play and he'll show us before the game what we need to do," Alderweireld added.

"The group is mature enough to play the way he wants and the technical staff is big enough to cope without him.

"Of course he will be missed but it's up to us to step up and deliver the performance he wants."