Neither Bognor nor Lewes could get on the scoresheet in this stalemate at Nyewood Lane – despite a lively, high-tempo match.
The Rooks were without ex-Rocks goal ace Terry Dodd, apparently nursing a sickness bug.
Bognor welcomed back Dan Thompson, starting his third spell at the club.
See our gallery of Chris Hatton’s pictures from the draw above - also included are Roger Smith’s pictures from Pagham’s 4-2 Cup defeat at Dorking.
The Rocks went close on four minutes when a cross by Ben Johnson fell to James Crane – but he headed over.
On nine minutes, claims for a handball in the area after Doug Tuck almost got through were ignored. Fraser Logan skied a Lewes chance well over the bar at the other end.
Jake Thomson tried his luck from 30 yards and forced a fingertip save from Rikki Banks, winning a corner that was dealt with.
Another Johnson corner picked out Craig Robson, who headed into the ground and saw it was easily saved by Banks.
Jack Dixon went close for the Rooks when he slammed in a low shot from ten yards, but Chris Winterton used his right leg to divert the ball away.
Logan made his way into the box for a shot from a tight angle. It rebounded out but eventually Winterton gathered.
Stuart Green set up Johnson but his low shot was straight at Banks.
Alex Parsons went close for the hosts with a shot from the edge of the box.
The referee had words with Phil Appiah, Robson and Dan Sackman after tempers flared, but no cards were shown.
Logan had two attempts thwarted when Robson headed away a shot and Crane followed up with a block.
Thomson spotted the keeper off his line from 35 yards but Banks tracked back well to save with two minutes left of the first half.
Johnson teed up Green but he poked the ball wide from six yards out.
Gary Elphick headed wide from a Dixon free-kick when it looked easier to score.
Lewes threatened when Nathan Crabb then saw his glancing header bounce wide from a Logan corner.
For Bognor, Johnson cut inside from the left and his low powerful shot was straight at a grateful Banks.
Thompson came on for Parsons on 65 minutes.
A Rocks counter attack ended with Thompson’s effort gathered by the goalkeeper.
Nice work from Whyte saw him make good headway into the box to pass to Tuck. The midfielder found Green, whose acrobatic scissor kick wasn’t good enough to beat Banks.
Thomson was replaced by Ollie Pearce in an attacking reshuffle.
In the latter stages, the game became scrappy and in truth neither side did enough to warrant the win – and neither side could argue with having to play Wednesday night’s replay – the winners of which will go to Ryman premier side Witham in the second qualifying reound on September 27.
ROCKS: Winterton, Warren (Medway 51), Crane, Tuck, Sackman, Robson, Whyte, Thomson (Pearce 74), Green, Parsons (D Thompson 68), Johnson. Unused subs: Morey, Boyle, Obamwonyi.
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