Full-time score from Hayes LaneSuper sub Lewis White stepped off the bench to claim a late winner as Millwall U23s made it three wins on the spin with a hard-fought victory against Crystal Palace U23s at Bromley FC.
White, a 37th-minute sub for Noel Leighton, was on hand to head home the decisive goal in this derby with just four minutes remaining in a game that also saw The Lions record a third straight clean sheet.
There were plenty of other plus points too, with defenders Shaun Cummings and Shaun Hutchinson getting a further 70 and 75 minutes of match action under their belts respectively.
Young centre-half Christian Mbulu was also back in the mix, coming on for the last 20 minutes of the match for his first game-time this season to ensure that it was smiles all round in the home camp come the final whistle.
The Lions looked bright in the opening exchanges and went close when a glancing header was sent wide of the target from a deep free-kick after three minutes.
Kris Twardek saw his inviting delivery claimed by Palace keeper Kleton Pemtreou as the home side looked to make the breakthrough, but it was Palace who created the first real clear scoring opportunity of the game.
Moments after Rian Bray had made an excellent interception at the back to thwart Jacob Berkeley, Andre Coker drove forward and squared to Corie Andrews, who contrived to fire narrowly wide of the mark.
Right-back Cummings was involved both defensively and in attack within the space of a couple of minutes, first sprinting down the flank and whipping over a dangerous cross that Pemtreou did well to hold and then lunging to make a perfectly timed interception from Coker's through ball.
Rian Bray fired in a low shot that was blocked and another Twardek cross kept the Palace keeper alert as Millwall searched for that elusive opening goal.
The home side went close to breaking the deadlock a couple of minutes before the break, but desperate defending from Palace kept out Twardek and then Gregg Wylde in quick succession following a goalmouth scramble.
Palace had the ball in the back of the Millwall net within four minutes of the restart after nipping in behind the Lions back-line, but his effort was ruled out for offside to the relief of the home team.
At the other end Kyron Farrell tried his luck from distance with a 35-yard free-kick seconds before Justin Skinner's charges had a loud shout for a penalty waved away by referee Mr Buonassisi after Kyren Mundle-Smith appeared to have been pulled down in the danger zone as he prepared to shoot.
Sub White was inches away from firing Millwall ahead just past the hour mark when he met Noah Chesmain's cross, but could only poke his effort wide at full stretch.
Wylde's chipped effort from the edge of the area was caught by the Palace keeper, who then reacted quickly to sprint out of his goal and head clear of the onrushing White as Skinner's men continued to try and find a way through the visiting defence as the game headed into the final quarter of an hour.
Palace always posed a threat on the counter-attack, however, and another impeccably-timed challenge from Bray averted the danger as Croker threatened to pull trigger.
That intervention epitomised the organisational qualities on display throughout by the home side, who were rewarded right at the death when sub White rose highest to finally breach the Palace defence with a textbook header beyond the keeper's reach.
Despite a late flurry of Palace pressure, the young Lions held firm for victory on a thoroughly satisfying afternoon at Hayes Lane.
Millwall: Girling, Cummings (Mbulu, 70mins), Chesmain, Donovan, Bray, Hutchinson (McNamara, 75mins), Twardek, Farrell, Leighton (White, 37mins), Mundle-Smith, Wylde. Subs not used: Sandford.
Scorer: White (86mins)
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