Bognor completed their fourth run of four straight wins inside a month to secure a top-three finish - and keep the Ryman premier title a possibility going into the final week of the season.
They are now guaranteed a home play-off semi-final at worst but if they win their last two, and leaders Hampton lose to play-off chasing Enfield next Saturday, it will come down to goal difference at the top.
Bognor have six goals to make up on Hampton in those last two matches.
Their first-ever win at Leiston came courtesy of second-half goals by Connor Tighe and Alfie Rutherford plus their fourth straight clean sheet.
Victory Road was a soggy spot to visit and the game had been threatened with being called off after heavy rain, but it survived and weren’t Bognor glad of it.
With Craig Robson still out through injury, Chad Field again started in defence. Doug Tuck and Dan Beck were in midfield as Gary Charman returned to the bench.
Early on Tighe tried a short pass into the area but couldn’t quite set up Rutherford.
At the other end Christy Finch failed to find any team-mate with a through pass.
Stuart Green teed up Harvey Whyte deep on the right and his cross was only just missed by the outstretched boot of Jason Prior just inside the box.
Beck’s cut-back to Prior led to his shot being blocked, but the flag was up for offside. Then Rutherford tried his luck, forcing goalkeeper Ashlee Jones into a good save.
On a pitch that was cutting up, Whyte’s ball to Rutherford won the Rocks a free-kick on 11 minutes. Beck’s kick was headed out to Tighe, whose deflected shot was saved.
Tighe’s neat cross was just too much for Rutherford and Tuck in the area.
Tighe won a corner on the right. Beck took it but Prior’s free header was stopped.
Kelsey Trotter slid in late on Whyte, earning a lecture. Beck’s free-kick was headed away. A Prior cross from the left was struck over by Crane soon after.
Green and Prior set up Tighe but his low shot failed to trouble the goalkeeper.
Good counter-attacking play saw Green find Tighe on the right flank. Tighe used his pace before firing a cross in that flicked the top of the crossbar but went out of play.
Bognor went close when James Crane’s cut-back pass found Prior and he slammed a low shot off the post.
Christy Finch found Jack Baker with a cross in a rare attack for the hosts but Baker’s header was wide.
Beck received a booking following a mistimed challenge on 33 minutes.
Trotter was shown a yellow card for a late challenge on Tuck. Beck’s curling free-kick was headed out for a corner.
Tuck tried his luck far out on the left but it bounced wide.
Rutherford was tripped up by Seb Dunbar on 38 minutes. Beck’s free-kick was again headed out.
A Beck corner had to be punched out by the right fist of Jones on 40 minutes as Bognor continued to create chances.
Tighe scuffed another chance after running square across the box.
Beck’s free-kick was curled on to the head of Prior but his effort spun over the bar on 47 minutes.
But Bognor took the lead on 50 minutes. A cross from Rutherford on the left rolled along the box – Green missed it but Tighe was on the back post to slot in, despite the goalkeeper’s efforts.
The Rocks extended their lead on 52 minutes. A neat ball forward by Tuck found Prior on the run and he set up Rutherford nicely – and the teenager composed himself before converting.
Beck’s free-kick was headed out for a corner. The corner was destined for Sami El-Abd but he couldn’t reach it and then Tuck was blocked.
Crane set up Rutherford as he ran into the box just after the hour but he hit the side netting.
Tighe was only just cut out on the edge of the area as Leiston defended desperately.
In the 65th minute Ottley-Gooch required treatment on a pitch that was worsening by the minute. Ottley-Gooch was replaced by Stuart Boardley for the hosts.
Good work from Field saw him find Tighe on the right but his instant cross flew out for a goal-kick.
Alex Parsons replaced Tighe and, for the hosts, Baker was replaced by Taylor.
Leiston were caught offside on 70 minutes as Heath progressed forward. The ball went flying over the bar moments later for the hosts.
On 75 minutes Snorre Nilsen came on for Beck for Bognor and Josh Cheetham replaced Trotter for the hosts.
Crane’s cross from the left found Prior but his looping header spun just over the bar and on to the top of the net.
A long ball forward by Whyte saw Rutherford smash an effort off the crossbar from a tight angle.
A cross by Heath on the left had to be headed back by Crane towards Smith but it went out for a corner. The corner eventually fell to Blake Saker but his low deflected effort was saved by Smith.
Ollie Pearce replaced the tiring Prior on 83 minutes.
Tuck smashed the ball well over the bar after some neat build-up by Crane on 86 minutes.
Rutherford’s looping cross dropped to Green on the back post and his header rattled the post.
Leiston had the ball in the net on 90 minutes after a cross found Jake Taylor but the linesman had his flag up for offside.
So next up it’s Brentwood at Nyewood Lane on Tuesday with a win and a few goals a must if Bognor are to keep up their faint title hopes.
Leiston: Jones, Saker, Dunbar, Trotter (Cheetham 75), Jefford, Bullard (c), Ottley-Gooch (Boardley 67), Heath, Baker (Taylor 69), Finch, Clark
Unused Subs: Groom, Rossis (GK)
Rocks: Smith, Whyte, Crane, Tuck, El-Abd, Field, Green, Beck (Nilsen 75), Prior (c) (Pearce 83), Rutherford, Tighe (Parsons 69)
Unused Subs: Wollers, Charman.
Attendance - 285
Match report by Liam Goodley
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