SHEFFIELD United manager Chris Wilder has confirmed that the club will send a letter to the English Football League and referees' body Pro Ref outlining their concerns following the decision to appoint Oliver Langford as referee for Wednesday night's Championship game at Portsmouth.
Over the years, the West Midlands official had been involved in a number of controversial moments in games involving the Blades - and sent off two players before half-time in the club's defeat at Charlton Athletic in January.
Langford again took centre stage in United's midweek 3-2 loss at Fratton Park after giving Hamza Choudhury his marching orders for two yellow cards in the opening half.
The second looked extremely harsh with the visitors having to play out the rest of the game with 10 men.
Afterwards Wilder voiced his concerns about Langford taking the game in the first place and questioned the refereeing pathway which he sees as preventing up-and-coming officials from taking games instead of 'survivor' referees of the ilk of the Midlander - in his view.
Speaking on Thursday, Wilder, whose side visit Bristol City this weekend, said: "I've spoke to our chief exec (Steve Bettis). And we're compiling a letter that's going into the EFL and to Pro Ref regarding our thoughts on all the things I've said and (we'll) see what the reaction is to the relevant authorities that will deal with it.
"I'm guessing there isn't... But I think it's pretty difficult that that referees us in the future.
"But that isn't my decision. I don't think it's fair. Maybe on the referee as well. To put him through that and put him under pressure.
"And to put him under pressure literally under 12 months ago, when he sent two of our players off controversially in the game against Charlton."
Ryan One is back in training ahead of the trip to Ashton Gate, but Matt Doherty will not be involved after having an injection in his knee and will be out for two to three weeks.
Jordan Ayew is close to being involved, as United faces a turnaround of less than 72 hours and Wilder is set to make changes.
On One, Wilder added: "He's training today and he'll be involved at the weekend, simple as that.
"We had to put some work into him in the international break and it was important we made him available for the game against Lincoln City and I think you saw the impact he made coming off the bench and always it's a medical decision from the experts.
"Of course I would have loved him to be involved, but we made a sensible decision and he'll be involved on Saturday."
As for Doherty, he said: "He's just had a little bit of a flare up with his knee over the last couple of weeks, so he's had an injection - so he's unavailable for the weekend.
"It's two or three weeks (out) with (also) the Derby and the Wrexham game, but it's not a long time."
Meanwhile, Wilder has confirmed that injury-hit utility man Jamie Shackleton has suffered a set-back in his road back to fitness.
Wilder said: "Jamie had another setback, so that's been a really disappointing period for him personally, as well as us. So we're just monitoring him as well and he's getting back up to speed, but he won't be available for the weekend as well.
"I've been vocal regarding players in the past and they don't want to be injured, but he keeps picking up some bits and pieces and he's more frustrated than anybody that at the moment he can't contribute regularly.
"He had a little spell where he got himself onto the pitch, but we're working with him and the medical team, working to get him back available."