There is something about this week and something about this competition. There may never be DVDs sold of this game but in any other round it would have stood out as an example of the surprising, dramatic potential of League Cup football.
Tottenham Hotspur were in command of the game with six minutes left, and the fans were singing about Wembley. It felt as if progression to the quarter-finals would be serene and deserved after a controlled performance.
The first 84 minutes might have felt slow but there was a whole game's worth of drama compressed into the final few. Norwich City had Grant Holt, Simeon Jackson and Alex Tettey off the bench to add experience and presence.
"You just wanted to bring a bit of energy in," Chris Hughton explained. "Tettey has energy in midfield, apart from a good defensive role, he can break forward as well."
A corner kick broke to Tettey on the edge of the box. He swung a volley which was flying wide before it hit Jan Vertonghen, himself on as a substitute. The ball was diverted back inside the post, beyond Hugo Lloris's reach.
"Sometime you need that little bit of luck," Hughton admitted. "Goals change games. Once you get the goal you have to go for it."
Events in Reading on Tuesday night proved the power of momentum in football and now Norwich had it. Two minutes later, with four minutes left, Robert Snodgrass took a long free-kick. Grant Holt headed it, Lloris saved, and Jackson gleefully pounced.
Of course, everything is in flux in the Capital One Cup. So Spurs surged forward again, hoping for an equaliser they did not think they would need. Kyle Walker went down in the vicinity of Marc Tierney and the assistant referee awarded the penalty.
"I thought the lad certainly made a meal of it," Hughton said. "Marc felt he didn't touch him." Clint Dempsey, playing in Jermain Defoe's position, took up his penalty role but Mark Bunn guessed right and saved. There would be no additional comeback here.
Villas-Boas was frustrated afterwards. He had seen his side dominate most of the game, Gareth Bale putting them ahead in the second-half with a perfect right-footed shot. Bale and Iago Falque, switching wings all night, had been the game's two best players but neither could find that second goal.
"It is a pity to see the game slip from our hands," Villas-Boas said. "We are obviously disappointed. Every top club embraces competitions to win it. We set out every game to win. There are always setbacks on the way to the final, big teams fall, we have fallen today but we move on from that."
Hughton, who said it was "immaterial" whether Norwich deserved to win, has the prospect of a last-eight game ahead against Aston Villa, managed by his predecessor Paul Lambert. "To beat a team with the quality of Spurs is a really nice feeling," he said "If you are in the quarter-final you are not so far away from the final."
Man of the match Bale
Match rating 6/10.
Referee J Moss (West Yorks).