The Scottish Communities League Cup last-four meeting will be the third time the Hoops have headed for the National Stadium as favourites in the last two seasons, with Kilmarnock winning through in the League Cup final and Hearts knocking out Neil Lennon's men in the William Hill Scottish Cup semi-final.
Now the Saints centre-back says it is vital that his side take confidence from the two upsets to bolster their belief against the Parkhead men – despite the fact they have yet to score a goal or record a win against Celts in eight meetings and have shipped an astonishing 22 goals in the process.
McAusland said: "Given what has gone before between us and Celtic, no one is giving us a prayer.
"But if you look at last season then it was the same for Kilmarnock in the League Cup final and also for Hearts in the Scottish Cup semi-final.
"What both these games show is that if you have a bit of luck, everyone plays to his best and Celtic maybe have a wee bit of a dip, then you have a chance. But what we have go to do at Hampden is play with belief and not be scared to try and play our game.
"I don't see much point in us sitting in as Celtic have so many good players going forward that they will always hurt you if you invite them on.
"This is a League Cup semi-final and they don't roll around too often for provincial clubs. So we want our supporters to get behind us."
The 24-year-old has been one of the SPL's most improved young performers this season and of late has been deployed, in preference to the more experienced Lee Mair, alongside Saints skipper Jim Goodwin.
The Buddies had strung a four-game unbeaten run before last weekend's 4-1 home defeat to Ross County, but McAusland has reassured St Mirren fans that the disappointing dip in form will not be carried into the tie with Celtic this Sunday.
He said: "Maybe the semi-final was a bit of a distraction ahead of the County game. Playing Celtic in a Hampden semi-final is something that is massive for all of the players and the club.
"It will be my first game at Hampden, if selected, and I am determined to make it an occasion to remember for all the right reasons.
"If Jim Goodwin and I stay at centre-back it will be great to have his experience. Everyone is determined to make sure we produce our best on Sunday."
McAusland is a boyhood Buddie, but revealed that the Saints support will be augmented by a group of Rangers supporters on Sunday.
The Saints stopper said: "My mates are all Rangers fans and I think they are all going on Sunday, so we will have two sets of fans cheering us on. No pressure there, then."
lSt Mirren last night signed 21-year-old Esmael Goncalves on loan from Portuguese Primeira Liga club Rio Ave.