Chelsea are still alive in the FA Youth Cup after victory at Leicester City.
The holders were frustrated for long periods but found the tie's solitary goal midway through the second half when Ike Ugbo powered in a header from Reece James's cross.
Still having not conceded in the competition, Jody Morris's side progress to make an eighth consecutive semi-final appearance.
Morris made two changes from our 4-0 win against Sheffield Wednesday in round five as Josh Grant and George McEachran replaced Luke McCormick and Joseph Colley in the side, with the Blues retaining their 4-3-3 shape.
The two sides had met just four days previously in the Under-18 Premier League but only 10 of the starters from that encounter, a 3-0 Chelsea win, started at the King Power, three for the visitors and seven for the hosts.