The SPFL have issued a firm warning to Celtic and Rangers over the use of pyrotechnics during the Premier Sports Cup final.

It comes after the two Glasgow giants and Motherwell were charged by the governing body over unacceptable fan behaviour at Hampden during the Premier Sports Cup semi-finals. Both games were delayed by the use of pyro with the Hoops' clash with Aberdeen held up by 14 minutes before Philippe Clement's sides clash with the Steelmen was subject to a five minute delay.

Going into Sunday's showpiece event, the SPFL have warned that any displays could impact on the "ongoing disciplinary process" facing both clubs. A statement read: "Final preparations are under way for Sunday’s Premier Sports Cup Final between Celtic and Rangers at Hampden Park, as the SPFL gets set to welcome tens of thousands of supporters for one of Scottish football’s showpiece events.

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"The SPFL is incredibly proud that it has the highest match attendance per capita in Europe and is committed to working with clubs and supporters to continue to enhance the overall matchday experience. The SPFL and Scottish FA have been in discussions after receiving requests to facilitate fan displays at the match.

"The Scottish football authorities are keen to support such requests, where appropriate, as such fan displays can enhance the matchday experience for all supporters in attendance. However, we have been clear with fans that while such displays will be accommodated, there remains a strict prohibition on smuggling pyrotechnics into the match, given they are illegal and pose clear risks to supporters, players and those working at matches.

"The SPFL, Scottish FA and both clubs are working with Police Scotland, and fans breaking the law by attempting to bring pyrotechnics into matches face a range of sanctions, including criminal charges and football banning orders as well as adding to the ongoing disciplinary process currently facing both clubs.

"As has been customary for recent Premier Sports Cup Semi-Finals and Finals, there will also be a pre-match organised display at the stadium, including the use of flame boxes ahead of the match kicking off. Such flame boxes are heavily regulated and used widely by sporting bodies across the world ahead of major events."

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