Amir Khan says the World Boxing Association granted him a rematch against Lamont Peterson because of "multiple irregularities".
They allegedly include "questionable decisions" by referee Joseph Cooper and mystery man Mustafa Ameen's "apparent intrusion into the scoring process".
Khan lost his WBA and IBF titles to Peterson in December after he was docked two points by Cooper.
He also alleged Ameen "interfered" with a WBA ringside official.
In a statement, Golden Boy Promotions and Khan Promotions* said: "Peterson's split-decision victory over Khan in Washington DC has been riddled with controversy as a result of a plethora of anomalies in connection with the bout, including:
- referee Joseph Cooper not counting a knockdown of Peterson and deducting two points from Khan for pushing (something for which points are almost never deducted), both of which ended up having a direct impact on the outcome of the fight;
- the ringside appearance of an unauthorised individual in Mustafa Ameen who apparently handled official scoring slips, seemingly communicated with fight officials throughout the fight and appeared to be photographed posing with a celebrating Team Peterson in the ring following the fight;
- and possible differences between the score sheet of the WBA and those of the IBF and the District of Columbia Boxing and Wrestling Commission."
The statement added: "Acting under its authority pursuant to WBA Rule C.26, the WBA concluded that the bout's outcome was impacted by referee Joseph Cooper's questionable failure to credit Khan with a knockdown in round one and his questionable decisions to deduct points from Khan in rounds seven and 12.
"As further cause to order the rematch, the WBA also pointed to Mr Ameen's apparent intrusion into the scoring process as well as possible discrepancies between the score sheets of the two sanctioning organizations and the local athletic commission.
"In its resolution mandating the rematch, the WBA went out of its way to note that, under normal circumstances, it would not disturb the discretionary function of a referee.
"However, in this case, because of the multiple irregularities, it was necessary for it to order the rematch."
Despite the WBA granting a rematch, Peterson could choose not to fight Khan and to relinquish the WBA title instead.
Khan gave his own reaction to the news, insisting he will prove to his fans that his defeat last month was illegitimate.
"I'm pleased that justice has been done and the WBA has ordered an immediate rematch. All we ask as sportsmen is for a fair and level playing field when we compete.
"Lamont Peterson proved in our fight that he is a great competitor and I hope that a second bout will be just as exciting.
"I want to prove without doubt that I'm the best in the 140lb division by taking care of business in the rematch."
Khan alleges that WBA official Michael Welsh suffered interference at ringside during the fight from Ameen.
The IBF has scheduled a hearing in Newark, New Jersey, on 18 January, but the organisation does not know whether Welsh will attend.
Asif Vali, Khan's business manager, says the IBF should also order a rematch.
"We're not saying something happened, we're not saying something didn't happen," said Vali.
"Mustafa Ameen will explain himself at the hearing and it will be interesting to hear what he says.
"Ultimately, one organisation [the WBA] have ordered a rematch because they feel some irregularities have happened on the evidence of what we've supplied them.
"If the WBA are [offering a rematch] then the IBF should do it as well."
The IBF has also confirmed to BBC Sport the identities of the panel that will hear the appeal.
Jack Reiss of California, Sam Viruet of New York - who are both referees - and Glenn Feldman, a boxing judge from Connecticut, will conduct the hearing.
The panel will have up to 10 days to deliver judgement and, if they allow Peterson to keep the IBF belt, a rematch is less likely.
*In a previous version of this report, the statement from Golden Boy Promotions and Khan Promotions was attributed in error to the WBA.