A place in the last 16 and a prize fund of £2,000 awaits the winners.
But manager Dave Carter is expecting a tough examination from the visitors.
Bristol Manor Farm top the Western League premier division and smashed Hengrove United 7-1 in the previous round.
‘This is a massive game for both teams, though we will go into it pretty much the underdogs,’ said Carter.
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‘We are only a few rounds away from a Wembley final and are not ready to give up on that quite yet.
‘Our aim is to get as far as we can.
‘And we must look to exploit home advantage.
‘I don’t think it will be very pretty because the pitch is likely to be very wet.
‘It will be a bit of a battle in the conditions.
‘But we went to Brimscombe and Thrupp in the last round with just 12 players and came away with the win.
‘Defensively we have been very sound and intend to give it our best shot.’
Carter has signed striker Blu Boam from Baffins Milton Rovers on dual-registration forms.
The new recruit will increase the attacking options.
Carter is also looking to bring in a couple more players to boost numbers ahead of the tie.
Some of his squad let him down at the last minute in their replay at Brimscombe when they found out they weren’t starting the game.
Not surprisingly Carter is not involving them this time around.
He is also forced to make a couple of enforced changes for the match.
Dan Gauntlett and Lewis Fennemore are both away.
Striker Robbie Pitman is now eligible after recently signing from Hythe & Dibden and Jake Morgan is back from suspension.
Carter is also pleased to see defender Jack Lee is making good progress in his recovery from injury.
Lee is getting fitter and fitter since his return a few weeks ago.
In the Wessex League premier division AFC Portchester will be looking to increase the pressure on the top two, Horndean and Salisbury.
Portchester take on Folland Sports at Wicor Rec (3pm).
Manager Graham Rix will be hugely disappointed if the Royals fail to take maximum points against the basement side.