Tony Choules is targeting another upset on Saturday yet he admitted victory in Uxbridge's FA Trophy tie could be the final nail in the coffin of their league campaign.
The Reds were among the pre-season favourites for the Southern League Division One South and West title but they never really recovered from a disastrous start which saw them bank only one point from the first 15.
Of course he will never throw in the towel but having endured a terrible Christmas spell in the league, culminating in a fourth defeat from six games, 10th-placed Uxbridge are 19 points off automatic promotion and even 10 points off the play-off places.
If the Reds win at home to Southern League Premier Division outfit Swindon Supermarine this weekend, they will be in the last 16 of the Trophy and the manager confessed he would have to contemplate concentrating on cup competitions, even if it is to the detriment of the league campaign.
"If it goes the way I want it to go I will have to sit down and think 'What do I do?' said Choules. "You'll be talking about being in the last 16.
"Our main task is promotion but the silly games we're losing means the title's slipping and the play-offs are slipping so maybe we'll have to concentrate on the cups.
"If we lose on Saturday the decision's made for me."
Uxbridge have been lucky to get three successive home draws in the Trophy and they have certainly made the most of it, upsetting Conference South clubs Dorchester Town and then AFC Wimbledon in the last two rounds, having previously knocked out Boreham Wood away from home.
By those high standards Swindon, third in the Southern League Premier Division, represent a relatively easy proposition as Uxbridge seek to improve on their history-making run in the competition.
"We've had an awful Christmas," admitted Choules. "The intentions were to have a Christmas that would give us a platform for bigger things but it's looking a long distance from us at the moment.
"We have not done ourselves justice but we've got to forget all about that and prepare ourselves for the biggest game in the club's history.
"I would like to think they'll treat us with some respect because of who we've beaten in the previous rounds and I've got the feeling we can pull something out of the hat on Saturday.
"I've said all along we have a squad that'scapable of competing in a higher tier of non-league football and our cup results suggest I'm not far wrong.
"We're the underdogs but we're confident."
Swindon's defeat at Gloucester City on New Year's Day was only their second reverse in 19 games in all competitions and only their fifth all season. They saw off Bracknell Town (4-2), Maidstone United (2-0), Bromley (1-0) and Blue Square Premier side Eastbourne Borough (1-0) to reach this stage of the Trophy and they are still right in the hunt for their league title, lying just seven points points behind leaders Farnborough with a game in hand.
Choules has just about a full squad to choose from with Mark Weedon (knee) due to be available in a week or two as well as recent addition Nathan Bunce, who is a month away from being match fit.
Melvin Baptiste and Matthew Fox have forced their way into the squad from the reserves and Baptiste has given Choules a selection problem with his performance at the weekend after standing in for Ryan Wharton, who was benched for his recent performances in games and in training.