Two goals by Terry Dodd - taking his season’s tally to 21 - took Bognor into the top six and left them just two points off a play-off place at a chilly Nyewood Lane.
Kane Wills got the other (see his cool finish in our video, above) and Bognor held out without too many scares despite having Craig Robson sent off midway through the second half.
It was Jamie Howell’s team’s third win in a row and sets them up well for Tuesday’s visit of fellow play-off hopefuls Lowestoft.
The Rocks were playing their first game of 2014, with recent downpours having claimed the encounters with Lowestfoft and Met Police that had been supposed to get their year under way.
The prolonged break had given one or two players time to get over injuries more fully, although Harvey Whyte and Doug Tuck, who are among those to have had recent niggles, were only on the bench.
Paul Hinshelwood started after joining Bognor on a non-contract basis following the end of his loan from Gosport Borough.
Bognor began the afternoon four points off the play-off pace. East Thurrock arrived in 20th place, three points above the relegation zone.
The Rocks were first to attack with the ET keeper called into action within two minutes, before the visitors failed to capitalise on a free-kick 25 yards out which was floated into the hands of Mark Zawadski.
It was a lively start from East Thurrock - who are also nicknamed the Rocks - and they looked intent on attacking, rather than sitting back, as some lower-placed teams have done at the Lane this season.
David Bryant had two bites at a chance after Leon McKenzie’s backheel played him into a good shooting position in the area.
The opening stages had the Rocks looking quite lacklustre and the away side were certainly the sharper operators.
Despite their slow start, Bognor took the lead in the 11th minute through Dodd. A throw-in on the right was played to him and he danced past two challenges just outside the area before firing an accurate left-footed effort beyond keeper David Hughes’ dive.
It was Dodd’s 12th league goal of the season and 20th in total.
East Thurrock were level within two minutes, though. Bryant’s shot hit Robson’s arm and the referee pointed to the spot and booked Robson. Left-back Tom Stephen’s kick beat Zawadski, despite him diving the right way.
Ben Godfrey had a run at goal but chose the wrong option in trying to pass to Arron Hopkinson, and the defenders got back to clear the danger.
After a fairly non-descript period, the Rocks regained the lead on 24 minutes. James Crane flew down the left when given too much space and swung a cross into the feet of Wills, who controlled it, turned and hit a low curling shot that beat Hughes.
It might have been 3-1 a couple of minutes later when two scrambles int the box just failed to bring another Rocks goal. Dodd had the best chance but couldn’t connect properly with a bouncing ball five yards out.
Dodd was close again, this time striking a fierce shot inches over the bar - and over the stand roof - after the ball had been laid back to him 15 yards from goal.
The goals had boosted Bognor’s confidence and they started to knock the ball about nicely, though East Thurrock still looked dangerous on the break.
The Rocks’ third came on 33 minutes when another flowing move ended with Ollie Pearce sending in a perfect cross for Dodd to head emphatically past Hughes at the far post.
Christopher Bourne attempted to fire East Thurrock back into it but his shot after a run across the 18-yard box threatened only the tiles on the roof of Seasons clubhouse.
A couple of hopeful balls into the Bognor box were all too easy for Zawadski to claim.
As had happened in the first half, the visitors were quickest out of the blocks.
East Thurrock scorer Stephens picked up a mystery booking during a hold-up in play three minutes into the second period.
Scott Chamberlain played Godfrey in on goal on 53 minutes at the end of a Rocks break down the middle, but Hughes got down well to block the shot and an offside flag went up in any case.
Pearce tormented his defender down the left on 58 minutes and another provided an another assist for Dodd, but this time the cross was just too long.
Dan Kempson replaced Pearce for Bognor on 59 minutes.
Dodd looked set for his hat-trick on 61 minutes when he controlled a Wills cross six yards out and shaped to shoot. When he did get his shot in, it appeared a defender had handled the effort on the ground - but no penalty was given.
The Rocks had a scare on 64 minutes when John was adjudged to have brought down Bryant only just outside the box. Bryant would have been in on goal but John escaped with a yellow card and the free-kick came to nothing.
Godfrey was next to go into the book - for a foul on ET right-back Jack Hopkins.
McKenzie forced an ET corner with a turn and shot that was bravely blocked. Then Bognor should have wrapped it up when Hopkinson and Wills broke, but Dodd couldn’t quite force in Wills’ cross.
Bognor went down to ten men on 71 minutes when Robson picked up a second yellow card for a late tackle just inside the Bognor half. It seemed a little harsh and Robson trudged off, unimpressed.
The hosts shored up their defence with Dan Sackman replacing Godfrey.
The one-man advantage put an extra spring in Thurrock’s step and they still felt they could get something from the game.
Staurt Axten replaced Crane with 13 minutes left for the Rocks to hold on.
ET replaced Lea Dawson with Tom Anderson.
Hopkinson streaked away from the visitors’ defence with ten minutes left but saw his effort come back off the base of a post. Then the same player forced an excellent fingertip save from Hughes after cutting in from the right and shooting.
Hopkinson was taking matters into his own hands and fired another shot at Hughes, but this one was a comfortable take.
ET made another change with Joseph Paxman coming on for Vaughan.
Dodd couldn’t believe he hadn’t completed his hat-trick on 86 minutes, dribbling through on the keeper but stabbing a shot wide from very close range.
ET were still pushing for a goal that would set up a grandstand finish but Bognor were defending resolutely.
Sub Anderson ran on to a square pass and fired a shot just wide from 20 yards in the final minute of the 90.
Rocks: Zawadski, Hinshelwood, Crane, Chamberlain, John, Robson, Hopkinson, Wills, Dodd, Pearce, Godfrey. Subs: Sackman, Axten, Kempson, Tuck, Whyte.
East Thurrock: Hughes, Hopkins, Stephen, Sammons, Easterford, Parmenter, Bryant, Dawson, McKenzie, Symons, Bourne. Subs: Anderson, Paxman, Dhariaal, Ring, Boswell.
Ref: A Moody
* The Rocks are in home action again on Tuesday when Lowestoft are the visitors.