The visitors went ahead on 41 minutes, added a second through a Callum Overton 67th minute own goal; and wrapped things up with five to go after Chi had been reduced to ten men following Lloyd Rowlatt’s dismissal.
Ryan Davidson returned to an otherwise unchanged starting XI from the one that came back from two goals down away at second-placed Ashford United last time out. Ethan Prichard dragged the Sussex side back into that match with a 70th minute strike before Emmett Dunn headed home a dramatic and deserved late equaliser in the fourth minute or so of additional time.
A long ball, which the hosts would rely on uncharacteristically here, almost found Josh Clack two minutes in but a defender got it back to keeper Aiden Prall.
At the other end Chi skipper Ben Pashley cleared Kweku Ansah’s cross and Ben Mendoza’s through ball towards Clack was just too firm.
A bit of skill from Kaleem Haitham got him away down the left but Prall was off his line swiftly ahead of Clack.
Kieran Magee dealt with a Frankie Morgan delivery and Oscar Housego failed to catch Magee out with the follow-up from some distance.
Overton then teed Haitham up only for his shot to skew wide of the mark.
Prichard, a bright light in the opening spell, jinked past a couple of players but delayed getting off a shot.
Lekan Majoyegbe fired one inches wide on seven minutes before a nice move involving Overton and Clack earned Chichester the first corner which Prall gathered under pressure from Dunn.
Next, Prichard drove down the right flank and fizzed in a decent cross towards Haitham, however defenders hooked it away.
And then another Prichard run into the box posed problems, but once again he took too long to pull the trigger and Corinthian smuggled the ball out for a corner.
Right back Ryan Davidson, who scored in Chi’s 2-0 win in the reverse fixture, headed this down and Dunn glanced an effort on to the bar.
Mendoza and Clack linked up in the subsequent attack for a corner which came to nothing before Magee’s route-one kick fell to Overton who dragged his attempt wide.
Super play from Rowlatt sent Davidson off down the right but there was too much on the final ball.
Prall had to cope with a back pass he didn’t want and somehow managed to get it away as Clack threatened.
Clack then brought Dunn’s ball down superbly only to have his cross blocked, and spurned the best opportunity of the half steering Haitham’s delivery over with a free-header on 26 minutes.
Davidson cleared a Housego set-piece moments later after Pashley impeded Oloyede and Majoyegbe dispossessed Mendoza midfield but his effort nicked off a Chi player and into Magee’s arms.
Pashley then gifted a wayward pass to Oloyede whose shot was bravely blocked by a teammate and on the half hour the Corinthian striker headed over.
Housego might have done better with an attempt eight minutes before the break that he pulled before Prichard’s determined run from deep in his own half opened things up only for Haitham to balloon an effort off target.
Ansah then wasted a chance for the away side with Magee stuck on his line but Dunn eventually managed to clear.
Housego and the impressive Morgan instigated a move on the left wing that won Corinthian their first corner which Jack Mahoney met unmarked at the far post with a header to break the deadlock.
Overton had a shot blocked as Chi sought to respond and Prichard couldn’t quite get a connection as another opportunity went begging.
Magee got to Morgan’s crisp delivery intended for either Oloyede or Housego before a Pashley slip set Housego up for a cracking shot which Magee saved magnificently, turning it round the post with his fingertips.
Chi’s performance in the second 45 was in stark contrast to previous week as they huffed and puffed and rarely troubled Prall who didn’t have a shot to save.
Some home side fans might have wished they too had left Oaklands Park at the interval like Kevin Pulley who headed off for a Paul Weller gig in Brighton.
One minute in the Corinthian keeper beat both Overton and Clack to the ball easily enough and Pashley cleared a set-piece after Housego was clattered.
Oloyede then wasted a glorious opportunity to double the lead when he got in past Dunn but blazed over.
The Corinthian No9 next collected Housego’s pass and forced a corner which Morgan whipped in and Magee gathered at the second attempt.
A break down the left involving Prichard and Rob Hutchings fizzled out and the visitors’ captain Jack Bath headed away Clack’s cross.
Housego’s free-kick picked out Ryan Sawyer but Magee got something behind his header for a corner which Hutchings hacked clear.
Mahoney then fired an attempt high over, only to be flagged offside anyway.
Oloyede bought another foul off Dunn which Housego once again delivered but no one could get a telling touch.
Dunn went shoulder to shoulder with Oloyede in the penalty area – nothing doing according to referee Luke Chapman.
Joshua Stirman replaced Ansah in the 65th minute sixty seconds before Overton, Chi’s top scorer with 14 goals in all competitions, inadvertently turned a corner past his own keeper to give Corinthian a 2-0 lead.
The hosts, with enough to do already, were then reduced to ten following a heated fracas as Rowlatt was brandished a rarer than hens’ teeth red card.
The Corinthian player who crashed into Chi’s midfielder escaped punishment, but James Billings was given a yellow for his part in the resulting flare-up.
Jack Holland’s cross evaded everyone on 71 minutes and Lewis Hyde was introduced for Haitham as the hosts rejigged.
Majoyegbe then headed a Morgan corner over and Magee gathered ahead of Oloyede.
Both teams rang further changes with Brandon Davey coming on for Billings, and Tyrone Madhani replacing Prichard.
Magee sent Hutchings away down the left but the Chi left back took one too many touches and the move petered out.
The hosts won a free-kick with five minutes of normal time left. Hutchings delivered to Davidson but the ball was cleared and then Davey and Oloyede carved up the middle of the park for Corinthian’s third and final goal.
Whether Magee could have been more assured, or Oloyede might have taken the ball out of the keeper’s hands, whatever, the 85th minute goal stood.
Eric-Georges Dellaud replaced Davidson in stoppage time and Mendoza struck an effort high over the woodwork before Housego pulled a fine stop out of Magee with the last kick of the game.
Chi are back on the road at Whitstable on Tuesday 5th April (Kick Off 7:45pm) and return to Kent on Saturday 9th April to play Herne Bay (Kick Off 3pm).
Chichester – Magee, Davidson, Hutchings, Dunn, Prichard, Pashley, Rowlatt, Mendoza, Overton, Clack, Haitham. Subs: (Carroll, Dellaud, Hyde, Moss)