Russell Martin has confirmed Swansea City will appeal the red card shown to Ryan Manning during the loss to Fulham.
The hosts competed well until the Republic of Ireland international was dismissed three minutes before half-time.
Marco Silva's men fully capitalised on their numerical advantage, scoring five times after the restart to earn an emphatic victory at the Swansea.com Stadium.
Fulham boss Marco Silva admitted, when watching in live play, he felt Manning's challenged warranted a yellow card, although he later revealed he understood referee Jarred Gillett's decision to produce a red after seeing stud marks on Wilson's leg.
The Irishman is now set to be banned for four matches, subject to an appeal.
And Martin - who says Fulham "dodged a bullet" after Swansea's impressive start - admits he could not hide his disappointment after Gillett sent off Manning in a decision that ultimately changed the course of the contest.
"It's the most important factor of the night isn't it [red card]," said the Swansea head coach.
"It's totally changed the game, I thought for 40 minutes we were fantastic. We were in control, we were dominant. The first 15 minutes was probably as well as we have started all season.
"I'm just really disappointed for the players and our fans.
"In my opinion, after watching it back it's a really poor decision. I think Fulham wanted a penalty a bit before that. They were adamant in the technical area it was a penalty. They got away with much more than I did with the fourth official.
"It is not high and it’s not reckless is what I got told at half-time. It wasn’t two footed and it’s not a lunge.
"What's happened is the referee has followed one mistake with the penalty, if he got that one wrong, I've not seen it back.
"I couldn't believe how quickly he got the red card out, so it's ruined the game in terms of a spectacle. It was two teams, really good teams, going right at it.
"I think we showed for 40 minutes that, on our day, we can be as good as anyone."
READ MORE: Swansea City 1-5 Fulham: Ryan Manning red card proves costly as Cottagers run riot
Aleksandar Mitrovic struck just 14 seconds into the second-half in south Wales following a mistake from goalkeeper Andy Fisher.
Ben Cabango then turned into his own net before Neco Williams added a brace to Bobby Decordova-Reid's header - with Joel Piroe scoring a consolation for the Swans.
It brought an end to the Swans' three-game winning run on home soil.
But Martin bemoaned his side's start to the second-half as Fulham further strengthened their hopes of gaining promotion into the Premier League.
"What the referee isn't to blame for is the start of the second-half which was really poor," admitted Martin.
"We follow that up with conceding another goal quickly. The mistake is on me. It shouldn't end up with Fish from a kick-off.
"The mistake is on me. We ask the guys to play that way. At times there's going to be mistakes, but the point is, it shouldn't be back to him away. To put the responsibility on him from a kick-off is madness.
"The game is done after that. We're playing against a team who are free scoring against 11 every week.
"But I'm really proud of the way they stuck at it and I think we scored from a set piece which gets that monkey off our back."
Swansea return to action against Blackpool in Lancashire on Saturday afternoon. Kick-off is at 3pm.
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