Millwall's young Lions put in a determined display at Thorp Arch on Monday afternoon as the final kick of the game saw Leeds United win 3-2 in a Professional Development League contest.
The Whites - who fielded a strong side including Ezgjan Alioski, Helder Costa and on-loan Arsenal striker Eddie Nketiah as a substitute, took the lead seven minutes from the break when Alioski's cutback was converted by Pascal Struijk inside the area.
After the break, Nketiah entered the fray and got his name on the scoresheet with a neat finish after Leeds broke down the left-hand side through Jordan Stevens with a low delivery.
With the hosts looking to slow the tempo down, The Lions won a penalty 15 minutes from time as George Alexander made a terrific burst with the ball into the area, brought down 15 yards from goal.
The striker took the kick himself and was initially denied down low to his right by goalkeeper Ilian Meslier, before pouncing to net the rebound and half the deficit.
Millwall were soon back level, as Billy Mitchell received the ball outside the area and let fly with a remarkable low drive which fizzed past Meslier into the bottom-left corner - a deserved leveller for The Lions who had battled hard against a strong hosting side.
But it was to be Leeds who played the final card, with Mateusz Bogusz firing a deflected free-kick past Ryan Sandford six minutes into injury time.
Kevin Nugent's youngsters sit sixth in the Southern Section of the Professional Development League after two matches.
Millwall: Sandford, Moss, Topalloj, Mitchell, Debrah, Ransom, Burey, Skeffington, Elliott, Alexander, Duncan. Subs: Muller, Fanshawe, Davies, Strachan, Bradbury.