Boro named a strong starting XI which included experienced defender Sol Bamba, so it was always going to be a tough test for the young Black Cats.
Anthony Patterson, who has played two league games for the senior side this season, started in goal for Sunderland and had a busy afternoon between the sticks.
Elliott Dickman’s side fell 2-0 down before half-time after goals from Harry Green and William Kokolo, while Josh Coburn added a third in the second half.
Sunderland pulled a goal back through defender Tyrese Dyce but it was too little too late for the hosts.
Our chief Sunderland writer Phil Smith has delivered his verdict on how each player fared at the Academy of Light – here are his marks from the game.
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1. Anthony Patterson - 7
Will be disappointed he couldn’t claim the first effort that led to the third goal, but otherwise was excellent and made a series of really good saves. One in stoppage time was breathtaking. 7 Photo: JPI Media
2. Kenton Richardson - 6
Got forward really well in the first half and his second-half assist was an overdue reward from some good crossing. Part of a defence that ultimately struggled. 6 Photo: JPI Media
3. Patrick Almond - 5
Showed his strength and composure at times but his defence found the second half in particular to be tough going. 5 Photo: JPI Media
4. Oliver Younger - 5
Won plenty of headers but caught out a little too often, particularly in the second half. 5 Photo: JPI Media