Martin O'Neill revealed Celtic were given a "general behaviour" warning by Police Scotland ahead of Sunday's League Cup quarter-final against Rangers at Ibrox.

There will be no Hoops fans in the 50,000-capacity stadium at the order of the authorities amid a ticket allocation spat between the two Glasgow giants. The spat is partly a result of the last Old Firm clash in Govan in March, which was marred by fans' disorder as Celtic won the Scottish Gas Scottish Cup quarter-final on penalties after a goalless 120 minutes.

The two clubs have both been ordered to play their next home Scottish Cup matches behind closed doors and have also been handed a £100,000 compensation bill, paid to whichever team is drawn as the away side in their next respective fixtures in that competition.

The 74-year-old Hoops boss admitted that "it'll be a bit strange not having the (Celtic) fans in but I'm nervously and excitedly looking forward to it; it's a great fixture" and also spoke about the police visit.

O'Neill said: "We had the police come in today, just a little 15-minute meeting with us, just reminders of our behaviour, which I think is actually a timely reminder. It's a good thing as well."

O'Neill, who confirmed midfielder Mika Baur will train on Saturday after missing training on Friday with a knock, has yet to decide whether late summer signing Sam Johnstone keeps his place in goal or makes way for Viljami Sinisalo, who started the season as number one.