Frank Lampard says diminutive teen star Billy Gilmour is "huge in talent" after the midfielder excelled in the FA Cup win over Liverpool.

Gilmour bossed Tuesday's 2-0 victory over the Premier League champions elect, the 18-year-old rightly named man of the match in just his second Blues start this term.

The Rangers youth product only stepped up to Chelsea's senior squad on a permanent basis last month but has already forced his way into manager Lampard's immediate plans.

"Billy showed today that he's absolutely comfortable at this level," said Lampard.

"If he can play like he played tonight then he's comfortable at this level, so he can get himself in and around the team now.

"The reason he moved from the academy to the first team building recently, to train with us all the time, is because of the quality of player he is.

"He's done himself no harm tonight with an immaculate performance, a brilliant performance."