Crystal Palace eased their way past Derby County to book their place in the fifth round to face either Stoke or Hull.
First half goals from Wilfred Zaha and Joe Goldsmith rounded off what was an impressive team performance and proved exactly why the Palace Academy is regarded so highly.
But the early stages of the first half were a little shaky for the home side as Derby's greater size and power seemed to unsettle a relatively small Eagles line-up. But once Palace worked out the Derby tactic of playing the ball to dangerman Ryan Connolly at every opportunity, the away side had very little else.
Of course that tactic almost worked out perfectly for John Perkin's side as the winger cut inside on his right foot and smashed a curling right footed effort against the bar.
However that was really the only highlight from the early exchanges. Connolly showed his threat with two decent crosses, but the Palace defence settled as the half wore on and quickly learned to deal with him.
As Palace settled they grew in confidence, and it quickly led to the opening goal.
Wilfred Zaha had already shown his threat with his pace when he slipped through the defence midway through the half, only to be flagged offside, but he got his timings much better soon after when he latched on to a through ball to fire home from just inside the box.
Derby then thought they had levelled things almost immediately when towering striker Callum Ball put the ball in the back of the net, but the linesman had already raised his flag for offside.
The striker had wandered into an offside position as the shot came in from the left and Mann parried it into his path.
With the Rams committed in Palace's half, the Eagles almost took advantage when Jack Randall carried the ball right to the byline, cut back with a neat piece of skill, looked up to see his support but couldn't find them with his pass.
But the home side got their second late on in the half with a brilliantly worked move. Sekajja sprinted into space on the right flank and played a low ball across the edge of the box to Randall who dummied it for Goldsmith behind him to calmly play it into the bottom corner.
Derby then came exceptionally close in the dying minutes of the first half to drawing a vital goal back, and it looked almost certain as Yohann Le Sant and then Ball were denied from close range.
The first came from Le Sant's effort eight yards out that Mann saved superbly to his right, and from the rebound Ball saw his effort from six yards deflected over by Alex Wynter on the line.
As it stood though Palace took a 2-0 lead into half time and richly deserved their ovation as they left the field.
In the second period Derby had their chances early on with skipper Jeffrey Hendrick let down by his first touch as he tried to control a cross in the six yard box, which allowed Mann to gather it quickly.
And they also came out with the obvious tactic of unsettling Mann from crosses with some rough challenges going in on the Palace keeper.
It almost paid off for when the Palace keeper did spill a cross, but there was a Palace defender there clear it off the line. From the resulting corner Henderick met it with a thumping volley that flew just over.
But the rest of the half was all Palace as the youngsters set about entertaining the crowd with beautifully crafted moves in and around the box, and were desperately unlucky that it wasn't rewarded with further goals.
Joe Goldsmith would have been disappointed when presented with the chance for his second of the night, but he struck his shot from 12 yards straight at the keeper. While Zaha was also denied his chance for a second when the linesman harshly adjudged him to be offside as he slipped through the Derby defence.
Just minutes later he was presented with a great opportunity 12 yards out, but he hit it straight at the keeper.
Randall then drew a fine save from James Severn soon after when the Palace midfielder, who had been a constant threat alongside Zaha and Sekajja all night, cut in on his right foot and curled a shot to the far post only to see the Derby keeper tip it round with his fingertips.
Derby, meanwhile, were reduced to speculative shots from long range with Connolly turning and firing over from 18 yards their best response.
As the game reached its final stages Palace were in full flow, knocking the ball round gleefully and with the confidence and style expected of individuals a good few years older.
And the only evidence of their youth was their lack of a killer finish to the set up play, which could cause problems futher on in the competition. But right now they are looking a very good side, playing very good football and looking good for their place in the next round.
Palace will now face either Hull or Stoke in the Fifth Round of the FA Youth Cup. These two clubs meet on Tuesday night and we will bring you full details of the next round in due course.
Crystal Palace: 1. Charlie Mann; 2. Kieron Kenlock; 3. Matt Parsons; 4. Alex Wynter; 5. Jerry Nnamani; 6. Jack Holland; 7. John Williams (Caprice); 8. Joe Goldsmith; 9. Wilfred Zaha; 10.Ibra Sekajja (Williamson-Murrell); 11.Jack Randall
Subs: 12 Jake Caprice; 13 Ross Fitzsimmons; 14 Rhys Williamson-Murrell; 15 Karl Knight ; 16 Malakai Field
Derby County: 1. James Severn; 2. Luke Garton; 3. Christopher Jones; 4. Yohan Le Sant; 5. Kallum Keane; 6. Meoi Abalimba (12. Aaron Cole, 45); 7. Aaron Dillon(Witham); 8. Jeffery Hendrick (c); 9. Callum Ball; 10. Graham Kelly (Wright); 11. Ryan Connolly
Subs: 14. Alex Witham; 15. Ryan Betts; 16. Kamahl Whight; 17. Sam McElory
