Lazio's stadium will be partly closed for their Europa League game against Celtic next month as punishment for racist behaviour by their fans.
It is the first sanction announced by Uefa since European football's governing body said the "football family" must "wage war on the racists".
Partial stadium closure is the minimum punishment Uefa can impose.
Lazio have been fined 20,000 euros (£17,300) and will suffer full stadium closure if they reoffend within a year.
The sanctions relate to incidents during Lazio's 2-1 win over French side Rennes in a Europa League group match on 3 October.
On Tuesday, Uefa defended its record of taking action against racism in the wake of England's Euro 2020 qualifier in Bulgaria, which was suspended twice because of monkey chants and Nazi salutes by home supporters.
Lazio said they might appeal against the punishment because it penalised the majority of their fans for the actions of a minority.
The Italian side host Celtic in their next European game on 7 November.