Fleetwood suffered a second successive defeat in the North Lancs / Cumbria League following their five straight wins.
Unlike against leaders Keswick the previous weekend, when Fleet let a 14-3 lead slip, the visitors were never in contention at Wigton and trailed 39-0 at half-time.
They showed character after the break to score two tries and Fleet would have won the second half but for a last-gasp Wigton try.
Coach Steve Woodburn said: “They are always good on their home patch and they hit us with everything.
“We lacked leadership and didn’t get anything right in the first half, but in the second half we went back to the game-plan and showed some spirit and character.
“It was as though we were trying too hard in the first half but it’s a young squad and we have to use the experience positively. We have to learn to do the right things when we are under pressure.”
Try-scorer Brad Stapleton impressed on the wing as did full-back Ali Cheal, while there was another hard-working performance by Scott Richardson, who has been selected for Lancashire Royals duty this week.
The league remains extremely tight, with only five points separating Wigton in third and Fleetwood in ninth.
It means Fleet could make a significant move up the table this weekend with a Melbourne Avenue victory over a Bolton side currently just one point and one place above them.