Ben Wilkinson’s side carved out a number of excellent chances – especially in a dominant first half – but found Seagulls keeper Tommy Reid in inspired form.
And a tight, hard fought clash was ultimately settled by a 73rd minute strike from Zak Emmerson whose long range strike beat City keeper Mikki van Sas to send the hosts into the fifth round.
Amidst blazing winter sunshine on the south coast, City dominated both territory and possession from early on
Adedire Mebude’s pace and trickery down the right wing was a potent weapon and on seven minutes it took a fine save from Brighton keeper Tommy Reid to deny the City winger.
Reid then had to be alert again on 10 minutes to divert another Mebude snap shot.
The Seagulls keeper then produced another superb save to deny Carlos Borges after Mebude’s inviting cross.
Brighton though were a threat, especially from set pieces with their aerial prowess and City were relieved to see Leigh Kavangh’s header from a corner just arrow over on the half hour.
There was another scare a minute later when Marcus Ifill got in behind the City defence only to send his shot wide of the target as he closed in on goal.
At the other end Reid then performed heroics once more to first somehow claw out Nico O’Reilly’s 40th minute goal-bound free-kick before denying Will Dickson’s almost instant follow-up.
The second half proved a cagier affair with space and time at more of a premium.
City keeper van Sas then performed heroics to deny Ifill on 72 minutes after the winger had breached the City defence.
But the hosts did force the breakthrough a minute later when Emmerson's long-range shot evaded the grasp of van Sas’s and found the top corner of the net.
City sought an instant response with Mebude firing over after Reid had flapped at a Barrington cross, but it was to no avail, with our FA Youth Cup dreams dashed on the south coast.
How we lined up
Ben Wilkinson’s youngsters are back in Under-18 Premier League North action on Saturday when we play host to Stoke City at the CFA.
Kick-off is at 12pm and the game will be televised live on CITY+.
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