Tottenham boss Mauricio Pochettino accepted his side almost paid the price for failing to kill off Sheffield United early in their Capital One Cup semi-final.

Christian Eriksen struck just two minutes from the end of a pulsating second leg at Bramall Lane as Spurs snuffed out a dramatic late Blades comeback to secure a 3-2 aggregate win.

The Londoners had seemed to be coasting towards a Wembley date with Chelsea as Eriksen opened the scoring, putting Spurs 2-0 up in the tie, with a sublime first-half free-kick.

But the clash turned on its head in the second half as 18-year-old Che Adams came off the bench and struck twice in quick succession to leave Spurs grateful for – and relieved after – Eriksen's late second goal.

Pochettino said: "I am very happy – happy for our players because they deserved it. It has been a big effort in all competitions, in all games, since the beginning of the season.

"I think that if we analyze the two games, the first and the second leg, I think we deserve to be in the final. But in football you need to kill – this is a lesson for us. When you create a lot of chances you need to kill.

"Afterwards the game changed and sometimes it happens, what we saw today."

Spurs appeared to be rocking after Adams' late introduction, with his goals after 77 and 79 minutes reigniting a passionate home crowd. Another teenage substitute, Louis Reed, then almost put the League One Blades ahead as he fired narrowly over after a fine run.

Pochettino said: "I was not worried, I think I was focused on the game and tried to find a solution.

"But in football you need to know that sometimes it happens and it is a good lesson for us. We need to learn. We have a young squad, young players who need to learn from nights like that.

"Now we are in the final we need to refocus on the next game."

Pochettino will now turn attention to other matters before focusing on his next attempt to beat London rivals Chelsea on March 1, but he is already looking forward to the clash.

He said: "I think it is one of the best teams in the world, Chelsea, but the final is only one game. All (things) can happen."

Opposite number Nigel Clough was proud of his players' effort but could not hide his disappointment after pushing the Premier League side so close.

Clough said: "It is disappointment first and foremost but underneath that is a lot of pride for how the players have gone about their task. To be so close to such a good side like Spurs – but just that little bit of quality they have got told on the night.

"I think if they play us off the park for two games and beat us 2-0 or 3-0 we hold our hands up but to come as close as we did makes it worse in many ways."

The tie appeared to be drifting away from the Blades at half-time, but Clough never gave up hope they could force their way back into contention.

He said: "We just said 'get a goal' and then it changes the game totally. We knew we needed two but we said just get one and then see what happens.

"The chance when we had them rocking at 2-1, if Louis Reed hits the target I think 3-1 might have done it. But we gave it a go, we gave them a run for their money.

"We just fell a little bit short, which is understandable given the two leagues, but it makes it worse when you come that close."

Clough was naturally pleased with the performance of Adams, but wanted to ensure the youngster remained grounded.

He said: "He is coming along nicely with the progress he is making. We think he has got a lot of potential at just 18 years old.

"But he has got to learn not to slide in the corner and celebrate when we need a goal. He has got to go and get the ball out of the back of the net and put it on the center spot. Little things like that he can improve on."