Hibs cited ‘wrongful dimissal’ in their appeal against the defender’s sending off against Aberdeen but the Easter Road claim was dismissed and an additional game added to his three-match suspension, ruling him out until mid-April.
Porteous fouled Ross McCrorie during a 63rd minute goalmouth melee, conceding a penalty converted by Lewis Ferguson in the 3-1 defeat for Shaun Maloney’s side.
The Hibs manager later claimed the dismissal was wrong as Portous had attempted to clear the ball, but the SFA stood by Alan Muir’s decision and added an extra punishment. However, the suspension will only be applicable to league matches and Porteous will be available for the Scottish Cup semi-final against Hearts next month.
Hibs said: “We can confirm that our appeal against Ryan Porteous’ sending off against Aberdeen has been unsuccessful. Our centre-back was dismissed after giving away a penalty in our defeat at Pittodrie.
“After receiving our appeal, we are disappointed that the SFA have deemed that there wasn’t a possibility for Ryan to play the ball successfully and have increased his suspension to four league games.
“That means he will miss our games against Dundee United and Hearts, alongside the first two matches after the split. He will, however, be available for our Scottish Cup Semi-Final against Hearts at Hampden.”
The red card was Porteous’ second of the season, though he was also retrospectively punished for violent conduct after an incident with Christian Ramirez when the sides last met in December.