An Ashley Robinson goal rescued a point for the Rocks at home to promotion rivals Folkestone at Nyewood Lane.
Bognor came from behind for a draw which ended their five-game winning streak. Second-placed Dulwich Hamlet and Whitehawk, in third, both won to close the gap - although the Rocks have a game in hand over Dulwich.
There was one change to the starting line-up after the 4-2 win at Godalming after Dan Beck was ruled out for the season with a broken collarbone. Harvey Whyte started on the right side of midfield after coming in on loan from Havant & Waterlooville.
Bognor could have taken an early lead as in-form Ashley Robinson had two great chances in the opening three minutes. First he skewed his shot well wide from inside the area after latching on to Ben Johnson’s chip, then he fell over a low cross from Whyte on the penalty spot.
The visitors had their first sight of goal in the 16th minute when Josh Burchell found himself in space on the left side of the box and his shot was palmed wide by Craig Stoner.
Robinson was involved again in the 19th minute when he dropped deep and played strike partner Steve Harper in down the left flank, but the big striker’s shot from the byline was pushed behind the near post by Jack Delo.
Folkestone again called on Delo to keep the scores level three minutes later as he saved Whyte’s first-time drive from James Crane’s pullback on the edge of the area.
Osa Obamwonyi, on loan from Sutton for the month, got himself in trouble after being robbed of the ball by the visitors’ top marksman Stuart King on the edge of the box.
Bu the striker ballooned his effort over Stoner and out of the ground, when he ought to have scored.
Johnson had a strong shout for a penalty turned down on the half-hour mark after was floored after twisting and turning inside the box.
In the following melee Whyte, who was looking impressive on the right wing, picked out Crane at the back post, but his header was comfortably saved by Delo.
It was Whyte again who laid on a great chance for Robinson to sidefoot home from close range, but he didn’t connect well enough and Delo saved with ease.
The hosts were dealt a blow on 30 minutes when Harper was forced off through injury. Terry Dodd took his place.
Bognor had strong shouts for a penalty turned down just before half-time when Whyte’s goal-bound header at the back post was blocked on the line by the arm of a Folkestone defender.
That seemed to invigorate the visitors who almost immediately got the opening goal of the game with a minute left of the half.
Big centre-back Liam Friend went on an unopposed run through the middle of the pitch, and had time to slide a through ball to King inside the box. The striker didn’t hesitate to stroke the ball under Stoner first time to the delight of the noisy following Folkestone fans.
The visitors could have doubled their advantage early in the second half. Burchell’s free-kick to the back post was cleverly knocked down by Roland Edge for King, who spun and volleyed straight at the well-positioned Stoner.
Bognor found themselves level in the 52nd minute through Robinson.
Whyte broke through the offside trap on the right flank and rolled it across to Dodd, whose shot was blocked. It span up in the air nicely for Robinson to head past Delo.
Four minutes later Dodd’s audacious scissor-kick bounced just wide of the left post from Johnson’s cross. Robinson also went close with a drive from the edge of the area that Delo claimed low to his right.
There were no shortage of chances for either side, but a surprising lack of killer instinct in front of goal for the division’s top two goalscoring teams.
Bognor were reduced to chances from set-pieces and long-range shots as Obamywonyi, Kane Wills and Robinson all had efforts.
Folkestone could have stolen all three points at the death as Darren Smith fired against the underside of the bar and James Everitt’s follow-up was cleared off the line by Obamwonyi.
Bognor are away to Burgess Hill next Saturday.
ROCKS: Stoner, Marzetti, Wollers (Andrews), Crane, Axten, Obamwonyi, Whyte, Wills, Robinson, Harper (Dodd), Johnson. Unused subs: Thompson, Porthouse, Boyle.