As Sutton pushed for an equaliser, the young Hammers held firm. Sean Tarima made a vital interception on 76 minutes to deny Nana Boateng after a slick Sutton move, keeping his side ahead at a crucial stage in the game.
The decisive second goal arrived with eight minutes remaining. Starting from the back, goalkeeper Herrick picked out Preston Fearon in midfield. Fearon turned and fed Swyer, who got away from his marker and drove forward before finding Ezra Mayers on the left. Mayers’ low cross found Ajala, whose first-time effort came off the inside of the post. The rebound fell kindly for Robinson, who was on hand to poke home and seal the points for West Ham.
Sutton continued to battle, but the Hammers managed the game well in the closing stages. Substitutes Brad Dolaghan and Sean Moore were introduced late on to help see out the victory, and the visitors did so comfortably earning a crucial three points to stay in contention for the National League Cup knockout stages.
Sutton United: Roberts, Okoli ©, Ransom (Eccleston 61), Odelusi (Moore 41), Coley (Tume 31), De Silva, Vaz, Boateng, Sivi, Jackson, Williams (Wadham 61)
Subs not used: Sims, Muller, Topalloj
West Ham United U21s: Herrick, Tarima, Golambeckis, Luizão, Robinson, Orford © (Akpata 61), Fearon (Moore 86), Mayers, Battrum, Swyer, Ajala (Dolaghan 87)
Subs not used: Hooper (GK), Rigge, Fawunmi, Caliste
Goals: Ajala 28, Robinson 82
Mayers: We've improved a lot in terms of dealing with senior teams' physicality
Playing in a more advanced role as a wing-back, Mayers reflected on an impressive team performance, highlighting the squad's progression in matches against senior sides.
“I think throughout the games against senior sides this season, the performances have been there, and we’ve certainly been getting better. I thought we played really well against Cheltenham, but tonight we took those lessons on board and put them into practice. The main thing is learning how to deal with the physicality, and I think we’ve improved a lot in that aspect.
“Even though I’m a defender, I love going forward. It was great to get that opportunity today as a wing-back. Playing alongside Preston [Fearon] and Lewis [Orford], who can pick out those passes in behind, suits me perfectly. With my pace, it’s a good combination!”