Their 1-0 defeat at Craven Cottage on Saturday night leaves the Blades 14 points adrift of safety and rooted to the foot of the Premier League.
Scott Parker’s men took a 61st-minute lead when Ademola Lookman fired past Aaron Ramsdale for his fourth goal of the season, as Fulham closed the gap to 17th-placed Newcastle to just three points.
The Blades had a penalty shout in the final minutes of the game, when home goalkeeper Alphonse Areola came flying out to deny Jayden Bogle, and Wilder claims the French goalkeeper was out of control.
“I’ve been told that they did (VAR review). If they have, well, it’s incredible because I don’t think there’s a more straightforward decision this season, in my opinion, it’s reckless, it’s out of control.”
The Blades have amassed just 11 points and just three wins all season, and Wilder claimed if it had been one of the bigger clubs in the division more would have been made of Areola’s challenge on Bogle.
“They are not that bothered, nobody’s bothered about us, the only person who is bothered about Sheffield United is me, when we come on to those meetings, me and the people involved in the football club,” the Blades boss said.
“There would be some comment and debate and discussion and moaning and groaning if that happened to one of the big boys. That debate tonight would have rumbled on forever and a day.
“But it doesn’t (for Sheff Utd). It just sort of gets pushed and understood and ‘they are having a moan’.”
Fulham recorded only their second home win of the season, with the first coming in a 2-0 win over West Brom in November, to close the gap to safety.
It followed on from victory at Everton and a hard-fought draw against Burnley in midweek, and Harrison Reed said Parker’s influence helped steady the squad after a difficult start to the season.
“At the start of the season, when we lost those first few games, all the noise (about Fulham struggling) was coming from outside the club and it was a question of not letting it affect us.
“The manager had sat us down before the season and warned us it was going to be a battle. We were going to lose back-to-back games, there would be outside noise about our prospects and our season would be defined by how we deal with that noise.
“From the start, he told us we are going to be fine if we stay level, stay grounded and stick together.
“We know this was a big win, and we know it’s been a big week because we’ve had to mix it up and show both sides of our personality as a team.
“At Everton we produced pure football, brilliant to watch and everyone was singing our praises. Then we had to scrap for our lives to get a point at Burnley, fighting for every second ball.
“This was not the prettiest win - but gritty or pretty, it was all about the result.
“Sheffield United are fighting for their lives like we are, but if we can put in more performances like that, we’ll have a chance.”
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