The three points put them level on points with Needham Market - whose game had been postponed the previous day - but on top thanks to a better goal difference.
It set them up nicely for Monday’s visit to big rivals Worthing (1pm).
They welcomed Brighton loanee Dylan Barnett back into the starting line-up and had youngster Oscar Haynes-Brown, a student from from Ardingly College who has represented England schools, on the bench.
In the second minute, James Crane’s pass picked out Ollie Pearce down the left. His cross found Jimmy Wild but his header flashed wide.
Calvin Davies stole the ball in midfield to pass to Wild. He composed himself before shooting low but it was well stopped by Seb Brown, a loanee from Chelsea, for the hosts.
James Harper bounced the home side’s first chance into the turf and Dan Lincoln saved after Met Police capitalised on a poor throw by Harvey Whyte.
Roman Michael-Percil steamed down the left to set up Sam Williams. From outside the box, Williams slammed his shot well over the crossbar.
Lloyd Macklin teed up Orlando Smith, who smacked it low amd wide of the right post.
Wild won a corner on 10 minutes and Pearce’s kick found Ed Sanders, whose header appeared to touch a hand in the area but the penalty claims were ignored.
Pearce’s cross flashed across the box but Wild wasn’t quite there to finish it.
Olli Robinson’s long throw had to be gathered by Lincoln – before Barnett hit a shot from long range, forcing Brown into a save.
Pearce’s corner on 20 minutes picked out an unmarked Sami El-Abd whose header was pushed over the bar by the goalkeeper. Soon after a Davies shot was deflected wide.
Pearce’s corner was punched out to Crane, whose shot was well blocked on 25 minutes.
James Fraser was booked as he threw the ball away. Then after Robinson’s trademark throw got headed out, the ball bobbled to Smith, whose shot bounced wide.
Following a Pearce corner another handball appeal went ignored as a shot from long distance appeared to hit a defender’s elbow in the box.
Wild couldn’t direct a header towards goal from a Barnett cross on 35 minutes.
Crane forced a fingertip save from the goalkeeper – then the same Rocks player’s incisive pass picked out Barnett, who curled it at goal, but Brown pushed it around the post on 40 minutes.
During first-half stoppage time, Ola Sogbamnu’s attempt from inside the area was well saved by Lincoln and the follow-up was also blocked.
Michael-Percil’s cross from the left was pinged to the back post but Crane was there to head it into the air and Lincoln gathered it.
Barnett won a free-kick for Bognor on 47 minutes. Barnett’s cross was curled into the heart of the area, but it flew through the crowded box and off for a goal kick.
A Macklin cross was well gathered by Lincoln before Barnett’s dipping cross was well stopped by the goalkeeper.
Sanders had to head off the line as Michael-Percil stubbed one at goal with Lincoln beaten on 55 minutes. Lincoln gathered the ball after Sanders’ heroics.
Michael-Percil went to ground under a challenge by El-Abd which was waved away by the referee.
Sogbamnu forced a parried save from Lincoln on 60 minutes before Davies was shown a yellow card for a foul.
Wild was replaced by Alex Parsons on 62 minutes.
Michael-Percil got himself into space before shooting low and committing Lincoln into a stop.
Charlie Collins and Dan Summers came on for Smith and Michael-Percil on 66 minutes.
Collins took a corner straight after coming on. He picked out Robinson, who headed just wide.
Davies was replaced by Chad Field on 68 minutes.
Barnett’s corner on the right found Fraser but his glanced header was narrowly off-target.
Field won it the ball in midfield to find Fraser. The midfielder passed to Parsons, who cut inside before seeing his shot deflected away by Brown.
A free-kick by Pearce had to be punched away by the keeper as Bognor continued to try to find a way past the stopper with crosses.
Parsons was brought down in the middle of the pitch by Harper, who was booked for the challenge.
Luke Robertson came on for Sogbamnu on 78 minutes for the hosts.
Doug Tuck was replaced by new player, Oscar Haynes Brown, who took to the field on 80 minutes.
A Barnett free-kick was dipping towards Field but a defender knocked it out for a corner which was cleared.
Whyte’s shot was deflected for a corner and the resulting kick by Barnett was headed away.
A short corner saw Pearce combine with Barnett before whipping it into the area, but Sanders’ header looped over the bar on 85 minutes.
Bognor won the ball again when a one-two move saw Barnett receive the ball from Parsons but his spinning attempt flew just over.
The rocks had been pressing for the winner and their travelling fans were in raptures when it arrived two minutes into injury time.
Parsons found space on the right and play the ball in low into the path of Brown, whose effort hit the post and then bounced off Steve Sutherland and in, sparking celebrations from the players and supporters.
There was no time for Met Police to rescue it and the Rocks could head home knowing they’d be top for the turn of the year.
Rocks - Lincoln, Whyte, Crane, Tuck (Haynes-Brown 80), El-Abd, Sanders, Fraser, Davies (Field 68), Wild (Parsons 62), Pearce, Barnett. Unused subs - Budd, Dolcetti.
Report by Liam Goodley
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