Looking to win the first trophy of Frank Lampard’s reign, Chelsea recovered from a woeful start at the King Power Stadium.
The Blues could easily have been behind before the break, but Lampard rang the changes at half-time and Barkley — one of the players introduced — grabbed the winner with a cool finish.
Chelsea’s quarter-final success could be a good omen for the Blues, who beat Leicester at the same stage en route to winning the competition for the eighth and most recent time in 2018.
Lampard made six changes to the team that handed the Premier League title to Liverpool with a victory over Manchester City on Thursday.
Chelsea were initially out of sorts as a result and Leicester’s Harvey Barnes had a sight of goal inside 30 seconds, the winger’s heavy touch letting the ball squirt away as he prepared to shoot.
It was a sluggish start from Chelsea and Blues defender Antonio Rudiger angrily admonished his team-mates after snuffing out a Youri Tielemans raid.
When Wilfred Ndidi was given acres of space to head straight at Willy Caballero, Lampard could be heard bellowing “liven up” at his sloppy stars.