Second-half goals by Ollie Pearce and James Crane earned Bognor their fourth win in six home games and lifted them back into the top half of the Ryman premier division.
They missed a host of goos chances and looked like having to settle for a point until Crane squeezed in a near-post header from a left-sided corner with five minutes left.
It was the Rocks’ first home game since Jason Prior’s loan spell ended but they were not short of forward options, with Pearce, Ashley-Paul Robinson and Stuart Green all in the starting line-up.
There was a late change to the team after Doug Tuck injured his groin in the warm-up. Charlie Oatway came in for him.
At a gloomy, murky Nyewood Lane it was one of the Rocks’ lowest home crowds of the season - 335 in total.
Green and Pearce almost capitalised on a weak clearance by Canvey keeper Tim Brown in the third minute but eventually the keeper got to a loose ball just ahead of Pearce.
Geoff Mitchell had the ball in the net for the Essex visitors after six minutes but he was clearly offside.
Victor Osubu tested Chris Winterton with a 25-yard free-kick before curling an 18-yard effort well over the bar.
The Rocks created their first real chance 12 minutes in. Robinson’s trickery on the left enabled him to cross to the near post, where Pearce’s flicked volley brought an excellent save out of Brown - a defender completing the clearance before Green could pounce.
Canvey suffered a second offside decision ruling out a goal on 16 minutes and in no time, a quick Bognor break ended with Robinson putting a free header wide from ten yards following a perfect cross from Pearce.
Jake Thomson’s deflected shot from 25 yards won a corner on 20 minutes. The kick fell to Craig Robson, who somehow volleyed it wide when it looked easier to get it on target.
Harrison Chatting’s energetic run at the Bognor defence on 24 minutes ended with a low, skidding shot that Winterton did well to hold.
Robinson was lectured by ref William Bull after losing possession on halfway.
Bognor were denied a clear penalty just after the half-hour when Pearce was bundled over on a powerful run into the box. The Rocks couldn’t believe it wasn’t given. Incredibly, Pearce was then booked for diving.
Johnson won a corner from a deflection with his 30-yard free-kick - ironically a decision that didn’t look like it should have been given the Rocks’ way.
The pressure was building on the visiting defence and Green and James Crane teed up Robinson for a shot deflected over the bar for a corner.
Canvey were still doing their share of attacking and Winterton saved sharply at his near post from a low Jack Simmons drive.
Another great chance went begging on 41 minutes when Pearce’s drive from a corner was not held by Brown, only for Green to head the rebound too high.
Same again two minutes later - this time Pearce shot over after Thomson and Green played him in with only Brown to beat.
Canvey were forced into a change when captain Jay Curran, who’d been injured in a challenge minutes earlier, was replaced by Marlon Agyakwa.
The home players were queueing up to take aim at Brown and Robinson was next to try his luck, whizzing a well-hit shot only inches over the bar from just outside the box.
The Rocks were straight on the attack in the first minute of the second half, Robinson drawing a fine diving save out of Brown with a rasping shot from the D. Then Green failed to control a lovely chipped through-ball from Johnson, allowing Brown to pick up.
Green got free in the area again but was eventually outnumbered by Canvey defenders and the chance was gone.
Mitchell put a free header over when a cross from the right found him, reminding the Rocks they could not afford to keep missing chances.
Everything the Rocks were doing seemed to be falling for Green - another run ended with a shot that didn’t trouble Brown.
Finally the Rocks found the net ten minutes into the second half. Dan Sackman was the unlikely inspiration for the move, surging into the Canvey half and playing a pass to Green on the right. His cross was right on the head of Robinson, and when his downward header was saved by Brown, it came out to Pearce, who poked it in - justice for the spot-kick he’d been denied earlier.
Bognor’s first change came on 59 minutes as Alex Parsons came on for Green.
Pearce had his eye in for a second on 62 minutes with a weaving run and low shot that went all along the floor and wasn’t far wide of Brown’s near post.
Robson missed another great chance from a corner a minute later, sending a free header well wide.
Crane was close to a spectacular goal when his 35-yard drive needed a deflection to take it over the bar.
Robinson was close to doubling the lead on 71 minutes, his curling free-kick after he was fouled 25 yards from goal being tipped around the post. Canvey defender Mike Jones was booked before the kick was taken, apparently for failing to retreat ten yards.
Anthony Thomas replaced Charlie Barlow for Canvey and the best effort they could muster as they looked for an equaliser was a bending shot by Agyakwa that Winteron saved comnfortably.
Canvey were level, though, a minute later. A corner was not dealt with and eventually the ball fell to Simmons at the far post, and his fierce shot took a deflection on its way past Winterton.
Both sides then made a change - Mitchell was replaced by Harrison Tweddle, while Omarr Lawson came on for Thomson for Bognor.
The Rocks were then forced into their final substitution - Johnson going down worryingly with an apparent knee injury, and George Branford coming on for him. Everyone will be hoping it is nothing like a repeat of earlier knee problems that have kept him out of the side for long spells in the past three seasons.
The Rocks were back in front six minutes from time as Crane squeezed in an 85th-minute header at the near post from a corner to the dlight of the home fans.
Canvey should have been level again a minute later but somehow three of their players failed to beat the man on the line after Winterton came out to deny an onrushing striker and was left stranded.
Robson was named man of the match - deservedly so for a commanding performance at the back.
Rocks: Winterton, Whyte, Crane, Oatway, Sackman, Robson, Green, Thomson, Pearce, Robinson, Johnson. Subs: Parsons, Lawson, Branford, Tuck.
Canvey Is: Brown, King, Carter, Barlow, Jones, Bryan-Edwards, Curran, Chatting, Osubu, Mitchell, Simmons. Subs: Agyakwa, Thomas, Tweddle, Slater.
Ref: William Bull (Winchester)
* Bognor will be away to Whitehawk in the third round of the Sussex Senior Cup - on a date to be confirmed.
Get all the latest from the Lane in the Observer, out on Thursday