Havant laid on a magnificent display to topple London one south leaders Medway 29-10 at Hooks Lane.
Head coach Will Knight rated it as his side’s best performance and result of the season as they kept their hopes of promotion alive.
CS Rugby 1863 now top the table on 87 points, one ahead of Medway with Havant a further seven adrift.
‘It was a brilliant team performance in which we played extremely well,’ said Will Knight.
‘To beat top of the league as convincingly as we did is very pleasing.
‘In a strange way we were disappointed because we could easily have scored another two tries at least.
‘This has to be seen as a big statement from us and I am sure raised a few eyebrows across the league.
‘Our goal is to finish in one of the top two places and earn at least a play-off place. That is our ultimate aim.
‘We felt very comfortable with the way we played. It was a big occasion for the club and all the players rose to the challenge.
‘We started well and pretty much maintained the pressure right the way through.’
Havant could not have wished for a better start as they opened the scoring inside the first minute.
After receiving the kick off, the home side launched an immediate attack which saw Darren Bamford side-step his way under the posts. Joel Knight added the conversion and the hosts remained on top before the break.
While Medway were pinned back in their own territory, Havant failed to make it count until late in the half.
Winger Jerome Rudder took a quick penalty inside his own twenty-two and quickly made ground before off-loading to Scott Morris to race in from 60 metres.
Within the first eight minutes of the second half, Havant stretched their lead to 26-0 with two more tries.
Ben Chambers grabbed the first following a good break by Joel Knight.
A quick change of direction from Bamford led to the next by scrum-half Nick Benjamin.
After the hosts had Harrison Young yellow-carded, Medway took advantage to hit back with two tries.
But once Havant were restored to full strength they resumed control.
Joel Knight completed the win with a last-minute penalty.
Will Knight said: ‘Under the circumstances that has to be our best of the season. We played a lot of good rugby and were very clinical.
‘It is satisfying to see players stepping up in the most important part of the season.
‘Our defence was superb and all the time we had 15 on the pitch Medway never looked like getting through.
‘We face another cup final against CS Rugby, who are the new leaders, in two weeks’ time.
‘It is another game we need to win if we are to haul the top two teams back in.’