Celtic manager Neil Lennon was given a six-match touchline ban by the Scottish Football Association on Tuesday.
Lennon had hoped to win his appeal against an automatic two-match ban and a charge of excessive misconduct after being sent to the stand during a game against Hearts on 10 November. But his appeal backfired as the SFA's disciplinary committee opted to treble his original punishment.
During the 2-0 defeat at Hearts, Lennon reacted angrily to the dismissal of midfielder Joe Ledley, while Celtic were also frustrated when a penalty appeal for handball was turned down - prompting a furious protest from the Hoops chief.
A statement from the SFA read: "Following a meeting of the Scottish FA's Disciplinary Committee at Hampden Park, the Celtic manager, Neil Lennon, was found guilty of excessive misconduct.
"Mr Lennon will serve his automatic two-match ban for being dismissed during the Scottish Premier League match against Heart of Midlothian at Tynecastle on November 10, 2010, plus an additional four matches for excessive misconduct. The sanctions are effective from Tuesday, January 18, and Mr Lennon has seven days to appeal the decision."
With Lennon's suspension beginning next week, he will still be in the dug-out for Wednesday's game at Hamilton and the weekend trip to Hibernian. However, he will be banned for the Scottish Cup fifth-round tie against Rangers at Ibrox.
Lennon, whose side are top of the Scottish league, will also have to watch from the stands for the Scottish League Cup tie against Aberdeen and four league games against Aberdeen twice, Hearts and Dundee United.
Celtic assistant manager Johan Mjallby added: "We are obviously going to miss him but we have to swallow that medicine and we have to take a bit more responsibility within the backroom staff. "It's a big loss but the players are professionals and some of them have seen that in the past at other clubs, when the manager is out for a few games. You just get on with it. I'm quite sure that Neil, from now on, is going to be a bit more calmer."