Second-half strikes by Ollie Pearce and James Fraser made it six points in four days as Bognor moved back into the Ryman premier top four.
It was fifth-placed Rocks versus 17th-placed Merstham at a clear but slightly chilly Nyewood Lane but the pre-match talk was that the Surrey side were a better team than their position suggested.
Merstham had most of the play in the first five minutes before the Rocks’ first threat, which came from a good Alex Parsons cross that the visitors cleared.
Pearce’s header was cleared off the line after Jimmy Wild hooked a Parsons cross to him inside the six-yard box in the eighth minute.
Dan Lincoln, making his home debut five days after signing to replace Billy Granger in goal, made a sharp stop to deny Charlie Penny after ex-Rock Aron Hopkinson crossed low from the right.
It was developing into a fairly even and lively contest but a couple of decent left-sided crosses from Dylan Barnett were all the Rocks had to show for their share of the possession.
On 20 minutes a slick one-two between Barnett and Pearce saw the full-back’s cross arrive at the feet of first Wild then Parsons - but both fluffed their efforts.
Bognor were stepping up the pressure and Calvin Davies whizzed a shot only just past the post from 20 yards.
Parsons was played in down the right on 25 minutes and surged into the box but had his low shot saved by the advancing Phil Wilson.
Hopkinson was yellow-carded for a late tackle on Dan Beck but the same player had a happier episode a few minutes later in forcing Lincoln to tip a long-range effort over and out for a corner.
Hopkinson was replaced by Alex Addai for the start of the second half as the home crowd hoped for an improvement from the Rocks, whose first-half efforts had been hurried at times, resulting in little work for Wilson to do.
Pearce did bring Wilson into early second-half action with a shot on the turn from just outside the box but it was a comfortable save.
Merstham’s Kershaney Samuels picked up an odd booking eight minutes into the second half, going into the notebook for taking his shirt off, with no-one too sure quite why he had.
Out of nothing the Rocks took the lead in the 55th minute. Wild worked himself some space for a 20-yard shot that the keeper got down to but could only parry back out, and Pearce was quickest to react to nip in and slot home.
Jimmy Muitt replaced Parsons two minutes later in the Rocks’ first change.
Pearce might have had a second with a curling shot on the hour but Wilson got down to save it.
A Pearce free-kick from the right was half-cleared to Gary Charman but his shot was deflected over.
Merstham brought on Tom Kasvanagh for Dan Hector in the 68th minute as the game became quite disjointed.
Sub Muitt tested Wilson with a run down the right and fierce cross-shot that the keeper took two attempts to hold.
Beck was replaced by James Crane with 16 minutes to go.
Merstham were looking increasingly dangerous as the half wore on and Samuels fizzed a left-footed shot inches over Lincoln’s bar with 12 minutes left on the clock.
Samuels’ next act was to be substituted, with Reese Hall replacing him.
Addai’s run and shot had Bognor worried on 82 minutes and the home fans were relieved to see it fly the wrong side - from Merstham’s point of view - of the post.
Bognor attacked looking for a second and crosses from either side of the box caused alarm in the visiting defence before being cleared.
Fraser was named MoM by the sponsors as the Rocks made their final change, bringing Chad Field on for Tuck.
Fraser lived up to his billing by diving low to head in the second right on 90 minutes from a left-sided cross by Pearce.
Rocks: Lincoln, Davies, Barnett, Tuck, El-Abd, Charman, Fraser, Beck, Wild, Pearce, Parsons. Subs- Budd, Field, Crane, Sanders, Muitt.
Merstham: Wilson, Abnett, Campbell, Samuels, Okoye, Douglas, Bennet, Vidal, Hopkinson, Penny, Hector. Subs: Kavanagh, Addai, Hall, Hogan, Willcock.
Ref: Alex Blake.
Report by STEVE BONE
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