Second-half goals by Doug Tuck and young sub Jack Parkinson earned the Rocks a hard-earned win against Brighton's youngsters on a night of great encouragement for the hosts at Nyewood Lane.
Tuck volleyed in a cross by trialist Cian Tilley just after the break before Pagham and Chichester College academy youngster Parkinson pounced for a late winner - and a decent-sized crowd will have gone home believing Jack Pearce and Robbie Blake's team fully deserved a creditable result.
Brighton's under-23s have just been promoted to the top tier of English football for their level of football but they certainly knew they'd been in a full-blooded game.
The Rocks gave a debut to Harvey Sparks, the utility player signed after he left Worthing, and welcomed back Dan Lincoln in goal - with another season at Bognor for the popular stopper apparently still a possibility.
The Rocks starting line-up also included defender Sam Rolf and playmaker Marley Ridge, who has joined on loan from Havant, while a host of youngsters, mostly from the Chichester College football academy, were on the bench.
It was also a first game as coach for Robbie Blake, recruited to replace Darin Killpartrick after leaving Pompey, where he coached under Paul Cook and Kenny Jackett.
The game started as so many friendlies do, with neither side exerting themselves too much. But Bognor were holding their own in the early stages against a Brighton side who looked comfortable on the ball, as you'd expect from a pro set-up.
The best early chance fell to ex-Worthing forward Jordan Maguire-Drew but his glancing header from a left-sided cross was wide of Lincoln's post.
A header by Bojan Rudulovic struck the post but an offside flag had gone up. Then Aaron Connolly turned and fired goalwards from 25 yards and it was not far wide.
Bognor were enjoying plenty of possession - probably about an even amount - and giving the Seagulls defence plenty to think about.
Tuck almost gave Bognor a spectacular lead on 23 minutes when a Calvin Davies cross was cleared to him but it flew marginally too high and wide.
With Bognor growing in confidence, Davies and Sparks teed up Tommy Block but he skewed his shot well wide.
Brighton took the lead in the 36th minute when Maguire-Drew curled an exquisite free-kick into Lincoln's top corner from just outside the area.
Bognor ended the first half on top, with Jimmy Muitt and Sparks unsettling the Rocks defence a couple of times and one Sparks cross having to be scrambled behind. HT 0-1
Brighton had a change of keeper for the second half, Billy Collings replacing McGill.
The Rocks brought on Tilley - who has made a bit of a name for himself at East Preston - in place of Tommy Scutt at the start of the second half and within three minutes he had set up the equaliser.
With Bognor on the front foot from the whistle they'd already seen one chance go begging before Tilley crossed to Tuck at the far post and he volleyed in despite a defender's attempts on the line to keep it out.
Tilley set up a couple more half-chances and Ridge was also showing up well in an attacking midfield role on a night which was giving plenty of encouragement to the home fans.
Davies went close to putting Bognor ahead with a low shot from 22 yards that keeper Tom McGill had to help around the post. Then Muitt went down under a challenge in the area but didn't get the penalty he looked like he deserved.
Brighton brought on Owen Moore and Viktor Gyokeres for Maguire-Drew and Rudulovic. Soon after that, Joe Tomlinson replaced Alex Cochrane.
Daniel Mandriou curled a free-kick over the bar for Brighton on 72 minutes.
A second Rocks sub on 75 minutes saw Jamie Carroll - a young attacking midfielder from the Chichester College football academy - replace Sparks, who'd had a reasonable debut.
Whyte almost scored a worldie with a shot from an angle from 25 yards after his own surging run into the Seagulls half.
Former Rocks loanee Stefan Ljubicic replaced Connolly with 11 minutes left.
In a Bognor change, young striker Parkinson came on for Muitt, who looked like he'd taken a bit of a knock.
Bognor ended the second half as they'd finished the first - well on top. Parkinson almost made a name for himself with a low shot from a cross that Collings had to be alert to get down to by the post.
Warren O'Hora was replaced by Ed Turns in Brighton's last change.
Then Parkinson DID make a name for himself with a fabulous turn and shot which sent the ball low past Collings and into the net for a winner that few could say the Rocks didn't deserve.
Rocks: Lincoln, Whyte, Davies, Tuck, Wood, Rolf, Ridge, Block, Sparks, Muitt, Scutt. Subs: Carroll, Tilley, Parkinson.