They increased their lead at the top of the table to 12 points although the chasing group have a game in hand.
The game kicked off in a hail storm and the heavy conditions proved to be a leveller throughout with most of the action being at close quarters.
Hoppers started well, causing problems at the first scrum and took the lead as early as the third minute as Oga Mabaya was driven over and Jake Squirrell converted.
But the lead was not to last long as a wild, speculative pass in defence set up an attacking position for the home side and a pinpoint cross kick saw wing Matt Loon catch and touch down unopposed and the conversion tied the scores.
A period of scrappy play involving a spate of aerial ping-pong followed.
And some physical exchanges led to the referee lecturing both captains.
But as the half drew to a close, Hoppers kicked a penalty to the corner and, from the line-out drive, prop Peter Altham claimed the try and Squirrel’s kick was good.
Mysteriously, Altham also picked up a yellow card in the incident so at the restart Hoppers were a man down.
Wirral dominated possession in the second period and laid siege to the visitors’ line.
But they were kept at bay by some awesome defending in which back row Matt Frings and the ever-willing Ally Murray were outstanding.
Hoppers got the worst of the referee Le Feuvre’s reaction to some further skirmishes.
They picked up two more yellow cards for lineout offences but the 13 men held out to claim an important victory.
After the game, a battered head player-coach Paul Arnold was full of praise for his players.
He said: “It was a great win in a very hard game against a side unbeaten at home.
“Leagues are won by results like this and, two men down, we showed magnificent spirit in keeping them out in the closing stages.”