Hawks host red-hot Dorking at Westleigh Park on Sunday just eight days on from being handed such a devastating defeat.
Oastler says Hawks were left 'shell-shocked' as fellow promotion hunters Dorking ran riot, with former Westleigh Park favourite Alfie Rutherford starring with a first-half treble against his old club.
But the Hawks skipper stressed suggestions the team were 'not trying' in the heavy defeat were wide of the mark - instead he just felt the 10-man visitors were blown away by a Wanderers juggernaut on the day.
And Oastler insists now is the time for the squad to show there isn't that much difference between eight-placed Hawks and fifth-placed Dorking when they meet at Westleigh Park.
He said: ‘We’re going into Sunday now and all the boys are raring to go. We need to put a few wrongs right and we need to play much better than what we did (at Dorking on Boxing Day).
‘Freak games like Sunday happen, it’s difficult to take, but we’re determined to make sure it’s a right result on Sunday.
‘I got beat 8-2 before, that was for Aldershot, I ruptured a knee ligament in the same game, so that was a lowpoint, but Sunday was the lowest I’ve ever felt after a game.
‘It’s almost like the game was a blur, it just bypassed us, I think the lads were shell-shocked more than anything - we got accused of not trying - it was just a case of being shell-shocked and everything happened so quick.
‘When you’re three or four-nil down away at Dorking with 10-men, it’s always going to be a difficult game.
‘We’ve got to try to forget about it now, the game on Tuesday (Hemel draw) was important, I imagine it’s going to be a different game on Sunday (against Dorking). We’ll be raring to go.’
Despite that damaging defeat at Dorking on Boxing Day, Hawks know a win over the same opposition in Sunday's home return fixture will see them move above Marc White's men in the NLS standings.