Teenager Ben Doak has signed a professional contract with Liverpool just five days after making his first-team debut.

The Scot, who turned 17 on Friday, came off the bench for an entertaining cameo in the Carabao Cup penalty shoot-out win over League One Derby last Wednesday.

Doak, who was signed from Celtic for £600,000 in the summer, has impressed in the youth teams, playing for both the under-18s and under-21s, where he has scored four goals and contributed four assists in helping Liverpool reach the last 16 of the UEFA Youth League.