A woeful defensive display saw Bognor's unbeaten start to the Bostik premier season end emphatically as first-half mistakes set up Folkestone Invicta for a 4-2 win under the Nyewood Lane lights.
Errors by three different Rocks players gave Invicta a 3-1 interval lead and it got worse when the visitors converted a SEVEN-YARD free-kick to go 4-1 up midway through the second period.
Jimmy Muitt and Tommy Scutt scored in each half for the hosts but it was a night Jack Pearce, Robbie Blake and their players will want to forget in a hurry.
It was the Rocks's first defeat in the league 11 games into the campaign and they will be anxious to bounce back when they host Margate on Saturday. They remain third in the table.
Bognor went into the game knowing a win would take them top but taking nothing for granted against a Folkestone team looking to end a run of four straight defeats.
Jimmy Wild was on the bench after making a surprise return to the club more than a season after leaving. Before the game Muitt and Harvey Whyte were jointly named players of the month for September.
The Rocks were quickly on to the attack and Joe Tomlinson and Mason Walsh linked up in the second minute but an offside flag went up.
But the Rocks were stunned to concede the opening goal in the fourth minute as a loose pass inside their own half by Tommy Block gifted possession to Ade Yusuff, who played a one-two with Kane Rowland and ran on to fire low beneath Dan Lincoln's dive.
Bognor tried to carry on as they'd started after the setback and a corner led to some desperate defending in the Invicta box. Muitt rifled a shot only just high and wide after another quick Bognor attack. Muitt was played in on goal by a Whyte pass on 12 minutes but the keeper advanced quickly and blocked his low shot.
The Rocks levelled on 21 minutes when Muitt was in the right place to volley in from only a yard or so out – and it was Walsh who made the goal. The winger seized on a poor backpass to go one on one with keeper Tim Roberts. Although his shot was saved he got to the rebound and curled it against the bar from a tight angle – with Muitt on hand to slam it home.
Bognor had not heeded the earlier warnings at the back and almost conceded a second within a minute of their equaliser. Then they were straight on to the attack and Walsh fired a cross beyond three Rocks players in the box. There was another scare for Lincoln when Sam Hasler curled a 25-yard free-kick only just wide.
Bognor had the ball in the net again but Lethbridge was offside as he took a Tomlinson pass in his stride and finished well. Kieran McCann threatened to put the Rocks 2-1 behind on 35 minutes when he beat his man and curled a shot goalwards from the angle of the penalty box, but it was high and wide.
Then Lethbridge got on the end of a long ball but poked his shot just wide as the keeper came out to meet him. But an error by Lincoln led to Invicta retaking the lead on 37 minutes when Rowland seized on hesitation at the back to slide it under the keeper and in.
Within two minutes it was 3-1 when Folkestone were awarded a throw that should have been Bognor's and again the Rocks struggled to clear, with a backwards header by Chad Field falling to Yussuf, who converted from close in.
The Rocks were shellshocked and as they tried to get back into it, McCann was booked for a lunge on Muitt. There were shouts for a Rocks free-kick on the edge of the box when a Walsh ball into the six-yard box hit a defender's hand but the referee ignored home pleas.
The Rocks didn't start the second half well and Doug Tuck went into the book for a foul on Rowland, again after the home team had looked brittle in their own half. Then Yussuf was close to his hat-trick with a volley that Lincoln was relieved to see go over.
Tommy Scutt replaced Block five minutes into the second half. A mazy Walsh run ended in a one-two with Davies that saw the winger go down in the box but the referee was having none of any claims for a penalty. Whyte blazed over from the rebound when his own shot was saved by Roberts after an incisive move by the home side.
There was another penalty call as Davies went flying running on to a ball into the box but again the ref was unmoved. Whyte almost connected with a wicked free-kick whipped in by Davies and soon another wave of home pressure petered out. Hasler was booked after cudely halting a Walsh charge down the Rocks left on 68 minutes.
Whyte stole possession as Bognor became increasingly desperate in their search for a goal but when he released Lethbridge the Pompey youngster ended up shooting horribly off target.
It was 4-1 on 73 minutes in farcical circumstances. Yussuf ran through looking for his hat-trick and when a defender touched the ball back to Lincoln the keeper had little choice but to fall on to the ball – giving Invicta an indirect free-kick seven yards from goal. Their first attempt was booted clear by Lincoln apparently after a Folkestone player had touched it, but the referee ordered a retake – to the Rocks' disgust – nd Hasler lashed it into the roof of the net.
The crowd came to life on 81 minutes when sub Scutt converted Lethbridge's cross after Davies and Muitt worked the ball into space down the right. Soon Whyte sniffed a chance of a third goal for the Rocks but he was denied by Roberts.
Folkestone replaced Rowland with Johan Ter Horst with six minutes to go. To their credit Bognor did keep going until the end and Tomlinson was only a foot or so off target with a left-footed free-kick from 25 yards.
It wasn't to be their night and if ever you needed evidence of how football's highs can quickly turn into lows, the way Bognor went from the euphoria of winning at Tonbridge to this poor defeat provides it.
Rocks: Lincoln, Calvin Davies, Tomlinson, Tuck, Field, Dandy, Whyte, Block, Lethbridge, Muitt, Walsh. Subs: Scutt, McCormick, Osborne, Wild, Carroll.
Folkestone: Roberts, Vincent, O'Mara, Newman, Callum Davies, Dolan, Hasler, Everitt, Rowland, Yusuff, McCann. Subs: Ter-Horst, Draycott, Paxman, Madden, Shaw.
Att - 508
Ref: Robert Ablitt (Fareham)