Will Gange's 14th-minute strike proved decisive as Wessex Division One Folland edged the quarter-final tie 1-0.
But Wilkinson was raging at the showing his side served up as they failed to reach the semi-finals of the competition.
The Baffins boss claimed it was 'one of the worst performances' since he arrived at the club in the summer of 2020.
And he felt his squad looked more Sunday League than Wessex Premier as they suffered a forgettable quarter-final exit.
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Wilkinson fumed: ‘We were a Sunday League team yesterday - we were Sunday League. The one thing I wanted to do when I came to the club was get that Sunday League mentality out of it.
‘A lot of them, when I first took over, they were playing Sundays - I see football as a job - so I always set standards.
‘The standards are we turn up on time, train properly, do it right, make sure training is fine. We try to look after you, we work hard in the process, we do things the right way and run it as professionally as we can for the level we’re at. It was a Sunday League effort.
‘That’s taking nothing away from Folland because they were far better than us on the day and deserved the win - full credit to them.
‘It was boring, disappointing and ruined my Saturday, to be honest. I’d have rather have been indoors building IKEA furniture!’
The only bright spot on a hugely frustrating day for Wilkinson was the performance of bright young left-back Ethan Gee.
And the Baffins boss insisted he felt 'sorry' the 16-year-old after a positive individual performance from the prospect at Folland.
Wilkinson added: ‘You want to win every match. You know your senior players and so-called starters are off it when a 16-year-old who played the whole match, Ethan Gee, was our best player, really.
‘I felt sorry for him because he’s having to listen to me go mad, shout at them at half time and after the game, when it should be a good experience and new football for him.’