He helped Leicester reach the 1961 FA Cup Final against Tottenham Hotspur, managed by fellow 'Scarborian' Bill Nicholson. The Spurs side also contained Malton-born Terry Dyson. Gillies made him club captain soon after, which saw him captain one of the most celebrated sides in the club's history as Leicester chased the double in 1962–63. Though it would eventually amount to nothing as Leicester eventually collapsed at the end of the league season and ended up finishing in a disappointing 4th position, the club then lost 3–1 to Manchester United in the FA Cup final.