Millwall bowed out of the FA Youth Cup at the Quarter-Final stage on Thursday night with a 1-0 defeat to Chelsea at Stamford Bridge.
Armando Broja's second-half strike sent The Blues through to the Semi-Finals.
Larry McAvoy and Chris Perry opted for a diamond formation in the midfield with Abdul Abdulmalik, fresh from England Under 17s duty, and Sean O'Brien spearheading the attack.
Chelsea were making most of the attacking play as the game went through its early stages, but The Lions stood firm, with Hayden Muller and Alex Mitchell marshalling the defence.
With nine minutes played Valentino Livramento had The Blues' first effort of the evening, but it was deflected wide. A corner was then flashed across the face of the penalty area but Millwall stood firm once more, despite three Chelsea players waiting at the back post.
Xavier Simons' deflected shot - which went behind - ensured The Lions' sheet was kept clean, but the ball was in the net with 19 minutes played; however, Armando Broja's overhead-kick was ruled out for a high foot on Millwall right-back Ben Bennett.
That was to spell the end of the evening for Bennett, who had to be removed, clearly suffering from concussion.
His replacement, Ezekiel Miller, was the first to penetrate Chelsea's penalty area on the half-hour mark, but after he lost the ball Lewis Bate went on a run that took in half the length of the field - he fed Broja, but the striker got his shot horribly wrong, skewing it wide.
The Lions were growing in confidence and forced a corner aftrer Jay Barton's goal-bound shot was blocked, but from the resulting corner taken by O'Brien, Mitchell nodded wide.
Simons curled over as Chelsea looked to up the ante with half-time approaching, with Borja finding the upper tier of the Shed End four minutes from the break after Leighton Fanshawe had to punch Chibuike Ezennolim's sliced clearance away from goal.
The Blues fashioned a couple of further chances as the opening 45 minutes came to a close, but The Lions held firm to go in at the break goalless.
Chelsea continued to apply pressure after the resumption of the second-half but could not find the net. Simons was the next to try his luck, but he found the upper tier behind the goal. On 62 minutes, however, after a lengthy stoppage for an injury to Levi Colwill, The Blues took the lead. A free-kick was swung into the box and controlled by Broja, who tapped home.
Miller had to be alert to stop a second for Chelsea shortly after, stabbing the ball behind despite the close attentions of Livramento, before Fanshawe saved well from Faustino Anjorin, before the Chelsea captain again had a chance but ballooned his effort over.
Penalty shouts for Millwall after Mitchell fell in the box were ignored by the officials, before the centre-back pairing of Mitchell and Muller both had headed opportunities spurned as the final 10 minutes got underway.
Try as they might, though, The Lions could not find the equaliser which would have forced extra-time, instead bringing down the curtain on a memorable Cup run as Chelsea took their place in the last four.
Chelsea: Askew, Lawrence, Simeu, Colwill (Rankine 61'), Maatsen, L. Bate, Livramento, Simons, Broja (Ballo 90'), Anjorin, Lewis. Subs not used: McClellend, Wady, Humphries, Harris, Fiabema.
Scorer: Broja 62'
Millwall: Fanshawe, Bennett (Miller 24'), Ezennolim, Munting, Mitchell, Muller, Barton (O. Bate 85'), Allen (Briscoe 68'), Abdulmalik, O'Brien, Boateng. Subs not used: Gillmore, Penney, Brooke, Walker.
Referee: Tom Reeves