Tottenham Hotspur reached the League Cup final after goals from Moussa Sissoko and Son Heung-Min sank Championship side Brentford 2-0 on Tuesday to set up a clash with Manchester United or Manchester City in April's showpiece match.
Fellow London side Brentford, playing in their first semifinal in a major cup competition, started brightly but fell behind in the 12th minute when unmarked French midfielder Sissoko headed in a fine Sergio Reguilon cross from the left.
The visitors, who had beaten four top-flight teams on their way to the semis, thought they had drawn level after the break when striker Ivan Toney headed home but the goal was disallowed for a very tight offside, which was spotted by VAR.
Toney's grounded knee was ruled to be offside before he rose to head in from close range after Ethan Pinnock nodded a cross back across the face of goal.
Jose Mourinho's Spurs side responded to that let-off with South Korean forward Son collecting a fine pass from Tanguy Ndombele and bursting goalwards before slotting past goalkeeper David Raya to make it 2-0 after 70 minutes.
Brentford's disappointment was compounded when Josh Dasilva was sent off six minutes from time for an over-the-top challenge on Tottenham's Denmark midfielder Pierre-Emile Hojbjerg, who was immediately substituted with blood streaming down his shin.
"It's a game that takes us to a final to, probably, but I hope not, an empty Wembley final but of course I'm very happy," said Mourinho, who has won the League Cup four times in his career -- three with Chelsea and once with Manchester United.
"The final is now in a pocket for three months, we have to wait for the final so we have to focus on what we have coming up... so let's forget the final for now. But when April arrives we have to be ready and to fight for the trophy," he added.
Brentford boss Thomas Frank added: "It was an open game, we had a top attitude, we were brave and an equaliser wouldn't have been a totally unfair result against a world-class team.
"If you want to go to a final against a top team, you need the margins with you but then they show class to get a second and after that it was game over."
Spurs have not lifted a major trophy since their League Cup triumph over Chelsea in 2008 but this will be their ninth final in the competition, which they have won four times.
The showpiece match will be held at Wembley on April 25, after the Football League moved the date back from February to increase the chances of fans being able to attend.
United host City in the other semifinal at Old Trafford on Wednesday.