Wild scored a superb goal on 18 minutes during an excellent first-half display from the Rocks. The second half saw them under pressure for long periods as promotion-hunting Leiston tried to rescue a point - but Jamie Howell's team clung on manfully to claim another win.
At the interval second-placed Havant were losing to Harrow but they recovered to win 3-1 - meaning it was vital that the Rocks got their job done too. They are guaranteed a top-four finish and close to securing a top-two finish, but the race for the title will go on for a few games yet.
It was another big game for the Rocks as they began the night top of the table with six games to go. Leiston arrived in fine fettle too, having risen to third place with a run of four wins and a draw from their past five outings. Bognor were first to show their attacking intent and a foul on Jimmy Muitt cutting in from the right gave Ollie Pearce a chance from a free-kick 25 yards out. He struck it well but it was too high.
Wild was a handful for the Leiston defence early on and looked like he was in on goal on five minutes. But he took one touch too many and shot over from a tight angle. A minute later the same player turned and ran at the visiting defence and shot low and only just wide of Ashlee Jones' left-hand post. The Bognor fans were in good voice behind Jones' goal as their team had the best of the early exchanges.
Harvey Whyte brought a fine diving save out of Jones when he burst forward an unleashed a right-footed drive from outside the box. The rebound almost fell back at his feet as he continued his run into the area. The Rocks broke the deadlock on 18 minutes - and what a goal it was from Wild. Fraser, Saturday's hat-trick hero in the 4-0 win over Canvey, played a neat pass to him just inside the Leiston half and he ran at his man, cut into the centre and rifled a superb shot from outside the area that flew past Jones and into the top corner.
Soon a Pearce corner found Gary Charman - still bandaged around the head after his weekend clash of heads - unmarked but his header was straight at Jones. Then Whyte broke up a Leiston break and found James Crane at the far post but his volley back across goal was eventually gathered by the keeper. Muitt went for the spectacular just before the half-hour when he met a long Wild pass on the volley from 25 yards. It wasn't a bad effort but it was over.Muitt was determined to get his name on the scoresheet and on 33 minutes he beat two men for sheer pace down the right before firing a cross-shot narrowly over the bar. A foul on Wild as Bognor attacked down the left gave Pearce the chance to swing a free-kick to the far post but it was just beyond Wild and Muitt.
Four minutes before the break, Wild forced Jones into a poor clearance to Fraser on the Rocks right. He beat one man and sae a left-footed shot deflected over for a corner. That led to a scramble from which Crane shot at goal but it was blocked for another one. The Rocks were doing all the attacking and the last chance of the half fell to Muitt, who saw a lot shot saved at the near post by Jones after Darren Budd set him up for a run into the box down the inside right channel.
Leiston began the second half by winning three corners in quick succession - having not had any for the whole of the first half. Their spell of pressure ended with a turn and shot by Adeyinka Cole but it was some way over Dan Lincoln's bar. Leiston full-back Seb Dunbar came off worst when challenging Whyte as the Rocks attacked down the right. Dunbar needed treatment and was shown a yellow card when he got up. The free-kick fell to James Crane in the area but he half-volleyed it over the bar.
Then Muitt won another free-kick in a similar position and earned Jake Hutchings a booking with another bustling run. This time Doug Tuck's free-kick was headed clear. The Rocks made their first substitution on 59 minutes when Calvin Davies replaced Budd.
Pearce got away down the left and sent over a teasing low cross that Muitt almost converted on 61 minutes - before Niko Muir had the Suffolk side's first shot on target at the other end, which was collected by Lincoln. Then Muir had a wonderful chance to equalise but he headed Matt Blake's cross over as Leiston caught out the hosts with a quick break. A double change for Leiston saw Joe Francis and and Jack Ainsley replace Hutchings and Cole.
Leiston had their tails up at this point and Lincoln got down sharply to push away a thumping Gareth Heath shot. It's amazing how often this season the Rocks have been on top but have then needed Lincoln to be at his best to preserve a lead. So it was here.
Alex Parsons replaced Muitt at the halfway point of the second half. In what, for the second half, was quite a rare Rocks attack, Crane and Pearce exchanged passes down the left and Crane's cross almost looped in under the bar after striking a defender - but the keeper held it. A lovely Pearce cross from the right edge of the box was flicked on by Fraser and almost put it at the far post but Wild but his instinctive touch on it was just too heavy.
Oscar Haynes-Brown replaced the hard-working Fraser with nine of the 90 to go. Wild's flicked header at the near post from a Pearce corner wasn't far off-target - then Leiston made their final change as Regan Pelling replaced Ollie Brown. Sub Davies was in the right spot to clear an effort off the line after Lincoln failed to gather a free-kick lofted into the box on 85 minutes.
Haynes-Brown almost forced a defender into an own goal as he tried to meet a ball into the six-yard box. There was a late flashpoint as Heath was booked for shoving into Whyte as he tried to stop them getting the ball back quickly after it went out for a Leiston goal-kick.
Three minutes were added on and Charman was forced out of the action with cramp just to add to the tension. There were more fisticuffs as Muir was booked for an incident in the Rocks area as Leiston had one last push for the equaliser - but it was an equaliser that, to the home crowd's relife, wouldn't come.
Rocks: Lincoln, Whyte, Crane, Tuck, El-Abd, Charman, Fraser, Budd, Wild, Pearce, Muitt. Subs - Davies, Parsons, Haynes-Brown, Dolcetti, Block.Leiston: Jones, Brown, Dunbar, Hutchings, Jefford, Bullard, Cole, Heath, Blake, Muir, Hubble. Subs: Ainsley, Francis, Pelling, Schaar, Beckwith.
* The Rocks now have two away games - they go to Enfield on Saturday and Sudbury a week later. After that just three games remain.
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