Sheffield United's Under 23s fell to a narrow defeat against Millwall after George Alexander steered home a Tom Elliott header with under 10 minutes remaining.
It harsh on a young Blades side missing several regular starters, who had put up a stellar defensive display against a strong Millwall side.
The opening 20 minutes at The Den were largely quiet, Millwall saw most of the ball but the Blades defence stood firm and looked relatively untroubled.
It was United who went closest when the chances did start to come, Sammy Ompreon's neat touch from Harry Sheppeard's cross finding him some space but his effort was blazed over.
Illiman Ndiaye fired an effort straight at the goalkeeper before the hosts broke upfield at pace, George Alexander curling an effort wide of Jordan Amissah's far post.
The second half was a more open affair but the goals still didn't come for either side. United started to get a real control on the game with 20 minutes to go and went closest of all when Reece York fired an effort from distance off the post.
Ndiaye soon forced the goalkeeper into a good save after a weaving run through the middle of the park but United still couldn't find the breakthrough.
The hammer blow came in the 82nd minute when Elliott rose highest from a Millwall corner and his effort hit Alexander who managed to turn the ball past Amissah.
The Blades tried to respond but couldn't find the equaliser they needed, Jake Young headed a Jake Kelly cross back across goal in the dying seconds but there was nobody there to turn it home.
Blades: Amissah, Sheppeard (J. Kelly 77), Mallon, Hall, Gomis, Ferguson, Trialist (Trialist 67), Ndiaye, Young, Ompreon, York.
Subs: S. Kelly, Neal, Ackroyd.