The boss breached Rule E3 by supposedly implying the match officials were motivated by bias with comments after the 4-0 loss to Manchester United on September 15
Wigan manager Roberto Martinez has had his appeal against a charge of misconduct rejected by the Football Association.
The charge related to the Latics boss’ comments after his side's 4-0 loss to Manchester United on September 15 that, according to the FA, implied that the match officials are motivated by bias.
A statement on the FA's official website reads: "The Appeal Board dismissed the appeal on 16 October 2012, having reheard the evidence in relation to the charge brought against Mr Martinez concerning his post-match comments following the Manchester United versus Wigan Athletic fixture on Saturday 15 September 2012."
The Spaniard did, however, have his initial fine of £10,000 reduced to £8,000 after new evidence was presented to the Appeal Board, which had not been seen by the original regulatory commission.
The 39-year-old had been upset by a number of Michael Oliver's decisions during the game at Old Trafford, with Danny Welbeck at the centre of controversy on the pitch.
Martinez felt the forward fell too easily under challenge from Ali Al-Habsi to win a penalty, as well as suggesting the England international could have been sent off late on.
"I have come to United three times before today and for whatever reason we don't seem to be measured in the same manner as the team at home," he told reporters.
"Today the penalty is as bad a decision as you are going to see in the Premier League. In many ways, you feel as though you are fighting against a mountain.
"There were tackles flying around that if they had been the other way round there would have been a couple of red cards."