PAOK Salonika and Rapid Vienna were hit with suspended one-year bans by UEFA on Tuesday after crowd violence before a Europa League playoff match.
PAOK won the first leg 2-1 last week after clashes between rival fans during the warm-up. The return leg is on Thursday in Vienna and will now be played behind closed doors.
PAOK will have to play their next three European home matches behind closed doors and have been fined 150,000 euros ($190,000). Rapid have been fined 75,000 euros in addition to the one-game, closed-doors sanction.
The one-year ban on the clubs is suspended for three years and allows the winner of the playoff to continue playing in this season's Europa League.
But either of the teams will be suspended immediately should any similar incidents occur within the three-year timeframe.
Dozens of PAOK fans spilled on to the pitch at the Toumba Stadium after flares were thrown by Rapid fans. Rapid said their fans were subjected to "almost unimaginable hatred" at the game.
Both clubs have the right to appeal and PAOK spokesman Kiriakos Kiriakos said the club intended to do so.
PAOK were charged with "the improper conduct of supporters - crowd disturbances, pitch invasion, setting off and throwing of missiles and fireworks - and insufficient organisation."
Rapid were charged with "improper conduct of supporters -crowd disturbances and setting off and throwing of fireworks and missiles."
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