Striker Dickson fired Ben Wilkinson’s youngsters into an early lead only for former City starlet Luca Barrington to level from the spot near half time.
However Ndala instantly regained the lead for City and further second half strikes from O’Reilly and substitute Muir sealed the deal.
What happened
Just as in our third-round game against Blackburn last month, there were icy temperatures and a snowy backdrop to the build-up at the Academy Stadium.
Fortunately, the snow had abated by kick-off and City were straight into our trademark possession-based game, dominating territory as we looked to stretch the Brighton backline.
And City’s early domination paid immediate dividends as we took a fine 14th minute lead through striker Will Dickson.
Left winger Joel Ndala was the architect, breaking free down the left flank as he latched onto Nico O’Reilly’s smart pass.
The winger then whipped in an inviting low ball and Dickson showed his predatory instincts, smartly applying a first time finish from eight yards out.
Justin Oboavwoduo then came within a whisker of doubling our lead on 25 minutes.
After robbing Charlie Penman of the ball on the edge of the Seagulls box, the City midfielder rifled in a low drive which was inches over the bar.
With the City pressure incessant, Brighton keeper Tommy Reid then did well to deny Ndala’s low drive on the half hour, diving low to parry away his goalbound shot.
Reid was there again five minutes to first block Emilio Lawrence’s fizzing shot with the City youngsters then disappointed to send the rebound wide from 12 yards.
Having weather that pressure however, Brighton began to grow into the game and City were made to rue our profligacy just before the break when the visitors levelled from the spot.
Referee Jonathan Maskrey adjudged that Brighton striker Bailey Smith had been bundled over in the box and awarded the penalty with former City starlet Luca Barrington converting from the spot.
It was a sucker punch but, to their immense credit, Wilkinson’s side summoned up an immediate response as we retook the lead in fine fashion through danger man Ndala in first half injury time
The winger drove at the Brighton back line from O’Reilly’s fine pass before cutting inside and firing into the top right-hand corner of the net for a magnificent strike.
Brighton were still a threat however and there was a 58th minute scare when Seagulls sub Josh Duffus powered a fizzing shot into the City side netting.
At the other end City skipper Jadel Katongo had a fine chance to extend our lead on the head, the central defender rising in the box to meet a fine Whittingham ball but sending his eight-yard header narrowly over.
City keeper George Murray-Jones then demonstrated his quality producing a stunning dive to deny Duffus’ curling shot that had goal written all over it.
City then carved out another gilt-edged opportunity as a teasing Jacob Wright cross found the unmarked Whittingham only for the defender to send his header over.
However, City finally claimed the all-important third goal on 75 minutes, Nico O’Reilly taking advantage of an error in the Brighton ranks defensive to score from close range.
And substitute Ashton Muir then sealed the win as he raced through to finish in fine style from another impressive attack by the hosts.
How we lined up
George Murray-Jones was in goal shielded by a back four of Lakyle Samuel, skipper Jadel Katongo, Max Alleyne and Matty Whittingham.
Our midfield trio was made up of Nico O’Reilly with Justin Oboavwoduo and Jacob Wright also alongside in the City engine room.
Our attacking trio was made up of Emilio Lawrence, Will Dickson and Joel Ndala.
CITY XI: Murray-Jones, Samuel, Katongo (c), Alleyne, Whittingham, Wright, Lawrence (Muir 45), O’Reilly, Oboavwoduo, Dickson, Ndala
Subs: Simpson-Pusey, Grant, Dada-Mascoll, Naylor, Harrison, Alpha-Ruprecht
BRIGHTON: Reid, Tasker, Mills, Penman, McConville, Hinshelwood, Moulton, Jenks (c), Smith, Mullins Duffus 45), Barrington (Bashir 75)
Subs: Lee, Fisher, Ryan, Albarus, Knight.
What it means
City’s reward is a fifth-round assignment at home to either Middlesbrough or Fleetwood Town.
Their fourth-round tie is being staged tomorrow night and fifth-round games are due to be complete on or before Saturday, February 11
What’s next
City’s Under-18s are back in Premier League North action on Saturday when we play host to Nottingham Forest at the CFA.
Leaders City will be looking to maintain top spot and CITY+ and Recast subscribers will be able to watch all the action live.
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