The dismal defeat to Derek Adams' men was the worst possible preparation for a Scottish Communities League Cup semi-final against a Celtic side they have yet to even score against, never mind defeat, since Danny Lennon took over as boss.
But McAusland believes a win against the Parkhead outfit in Sunday's Hampden fixture would be the best possible way to make up for last week's calamity against the Staggies in Paisley.
He told Press Association Sport: "To get beat 4-1 by anyone at home is shocking so we really need to kick on this Sunday. I've tried not to think about that game too much. I've tried to erase it from my memory. It's hard to do that though as the gaffer has been on our case a bit. You also feel guilty about the fans who have paid money to come and watch that.
"But we have a chance to try and repay them, more so as it's not just another league game. The fans are looking for us to do that and we owe it to them to reach the final."
Finding their way past Celtic will not be easy given the Buddies lamentable run of form against the Glasgow giants since Lennon was named Saints' manager.
A 4-0 thrashing ended former Parkhead boss Tony Mowbray's reign but since then it is Lennon's namesake Neil who has ruled the roost, racking up a 22-0 aggregate scoreline over eight games.
But McAusland insists the burden of expectation could play against Celtic: "In our last two performances at Parkhead and in a few other games against Celtic, we have been battered. They beat us 5-0 earlier in the season and there is no doubt we have been poor against them.
"But if we can put a performance together for ourselves, our families and the fans, hopefully, we do something come Sunday.
"We're obviously the underdogs and Celtic will go into the game thinking they have battered us the last few times. But there will be more pressure on them to win than there is on us. We just need to put on a performance for the fans and hopefully come away with a result."