The Rocks crashed to their first away league defeat of the season - and their third loss in a row - as high-flying Kingstonian struck four past them.
The Rocks took an early lead through Dan Smith but after that they struggled and eventually caved into the Ks' attacking prowess.
It leaves them 12th in the table and looking short of confidence - and short of players after being able to name only two subs - ahead of next Saturday's visit to face deadly rivals Worthing.
Defender Ed Sanders has returned to the club from Whitehawk and went straight into the team in the match at Corinthian Casuals' ground, the King George V Stadium. The rain was persistent and the wind was howling across the field as the players kicked off.
Chad Field did well enough to shield off Delano Sam-Yorke on two minutes when Harvey Whyte's pass went astray. And Bognor took the lead on four minutes when a great move ended in Jimmy Muitt's cross picking out Smith, who hit it low and into the bottom corner.
Kingstonian responded quickly to equalise on seven minutes. James Daly combined with Sean Clohessy before running square and hitting it early with his left foot and his shot beat Dan Lincoln from outside the box.
They continued to come at the Rocks and Elliott Buchanan went close with a near-post effort from Clohessy's cross on 11 minutes. Muitt's free-kick after Bradley Lethbridge was fouled just wouldn’t fall for Sanders, who was put off by Rob Tolfrey. A good build-up led to Ben Dempsey shooting narrowly wide.
Clohessy – a threat all afternoon - got the ball to the back post but Louie Theophanous couldn’t get the ball back across goal and it was cleared. But the Rocks went behind after they gave the ball away deep in their own half on 18 minutes. Shaun McAuley latched into it before shooting it low beyond Lincoln.
Joe Tomlinson’s cross was too high for the leaping Smith in the box after Lincoln had denied Theophanous at the other end. Buchanan found Theophanous with a pass on 28 minutes. Theophanous ran on before lashing it low into the bottom corner beyond Lincoln to give Kingstonian a bigger lead.
Jay Glasson forced Lincoln into a one-handed save, pushing the ball around the post. Muitt held the ball up for Lethbridge but he blasted well over the crossbar. Lethbridge had another go at goal on 39 minutes but under pressure he could only roll it harmlessly to Tolfrey, who easily saved.
Dempsey hit another chance high and wide from outside the box as the Ks pounced again and they were deservedly were 3-1 up at half-time.
After the break Muitt's low cross was bound for Tomlinson but a defender did enough to put him off. Another cross flew out of play from Muitt following a short corner. Sanders hacked a shot off the line when Lincoln was stranded as the rain got heavier, making passing football difficult.
Field gave away a free-kick on 58 minutes just outside the area. Buchanan stepped up and curled the ball over the defensive wall and it neatly dipped into the net, giving Rocks a 4-1 deficit and making it a real uphill struggle to salvage anything from the game.
Doug Tuck smacked the ball well over the crossbar following Muitt's low cross along the deck. Another Muitt cross fell to the feet of the onrushing Tomlinson, whose strike was well saved. Sanders tried to clear but the ball flashed towards goal and forced Lincoln into a reaction save. Muitt's direct free-kick bounced in front of Tolfrey but he did enough to push it away just out of Tommy Block's reach.
Buchanan blasted over before Clohessy's cross picked out Buchanan on the back post. But another great save from Lincoln steered the ball wide on 77 minutes.
Lincoln got his fingertips to another long-range effort by Dempsey following a cross by Theophanous. A great save kept the score to 4-1 near the end.
Bognor couldn’t reduce the deficit as they fell to their first league defeat of the season away from home against a very strong and experienced Kingstonian.
Rocks face their big Sussex rivals Worthing on Saturday (3pm) at Woodside Road and will hope for a better performance - and a bigger squad to select from.
Rocks: Lincoln, Whyte, Tomlinson, Tuck, Field, Sanders, Scutt (McCormick 67), Block, Smith, Muitt’s, Lethbridge (Osborne 71).
Att - 310