Liverpool supporters were no doubt hoping for a solid display from Michael Carrick’s Middlesbrough, to see them through to the final, but it didn’t ensue.
While the away team threatened in the opening few minutes, Chelsea then dominated, taking advantage of mistakes on the ball and ultimately winning 6-1 on the night.
On that occasion, Vladimir Smicer, Igor Biscan, Robbie Fowler and Danny Murphy (2) all scored as the Reds took another step towards the treble.
The title for biggest win on aggregate in the semi-final goes to Man City, who beat Burton Albion 10-0 in 2019, after an incredible 9-0 first-leg victory.
On Tuesday, Enzo Fernandez and Cole Palmer both scored, with the former netting twice in a man-of-the-match display. Axel Disasi and Noni Madueke also bagged, as well as Jonny Howson who scored an unfortunate own goal.
Morgan Rogers at least gave the Middlesbrough fans something to celebrate, though slightly in jest, when he curled in an 88th-minute consolation in front of the travelling supporters.
Fulham have never progressed this far in the League Cup and have never won a a major trophy. Their last major final was in the 2010 Europa League, when Roy Hodgson’s team were beaten 2-1 by Atletico Madrid.
This year, the League Cup final will take place on Sunday, February 25, at Wembley.