Barry Douglas and Nicky Riley must serve red card bans
Dundee have failed with an appeal against Nicky Riley's red card in Saturday's win over Hearts.
And rivals Dundee United met with the same outcome as they contested Barry Douglas's weekend dismissal.
Both players will now serve the customary two-match suspension.
Following United's 1-0 loss to Ross County, manager Jackie McNamara said: "It's not a red card and it's frustrating. I didn't even think it was a yellow card."
Douglas was sent off by referee Kevin Clancy following his sliding challenge on County goalscorer Ivan Sproule.
Riley, who came on as a second-half substitute, was dismissed near the end of the game at Dens Park after a tangle with Hearts defender Kevin McHattie.