Erik ten Hag shortlisted three young academy stars for promotion to Man Utd first team
Williams was joined in the session by academy teammate James Nolan, who also worked with first-team players.
Nolan, who just turned 17, has one goal for the under-18s this season.
Manchester United boss Erik ten Hag is preparing his team to face Aston Villa in the Carabao Cup tonight.
Part of this preparation involved an expansive training session with young players mixing with first-team stars.
A notable call-up was 16-year-old forward Ethan Williams, fresh off a brace against Arsenal for the under-18s at the weekend.
Williams posted a message on Instagram which joked that he had enjoyed the kickabout.