Hearts were yesterday given a week to pay outstanding monies to their players by the Scottish Premier League.
An SPL subcommittee met after the Scottish players' union, PFA Scotland, submitted a formal complaint on behalf of Hearts' first-team squad on 16 December, when wages were not paid on time for a third consecutive month.
Last month's pay remains outstanding and the SPL has made a series of demands in order to clear the financial uncertainty surrounding the club. A league statement read: "An SPL board subcommittee today adjudicated in the dispute between 14 players and Heart of Midlothian FC. The SPL board subcommittee has ordered December wages to be paid by 11 January.
"Interest on all sums overdue from October, November and December wages must also be paid by 11 January. January salaries must be paid on time on 16 January.
"The club must also pay the claimants' legal expenses and the SPL's costs of today's hearing. Both sides have the right to appeal the decision to the Scottish FA within seven days."
Should Hearts fail to meet the deadline, fresh disciplinary proceedings would be opened, with unlimited sanctions available to the SPL at that point. The SPL's chief executive, Neil Doncaster, said: "Today's decision demonstrates how seriously the SPL take late payments of wages to players."
Hearts have avoided answering questions on the subject as a result of a media blackout, which has been in place since 22 October. The club this week partially lifted that by speaking to match broadcasters after their 3-1 Edinburgh derby win at Easter Road.
The club's manager, Paulo Sergio, told BBC Scotland that he was expecting a difficult month, with players expected to depart during the transfer window to reduce the wage bill.
Eggert Jonsson has already joined Wolves and Ryan Stevenson is on self-imposed leave with six months remaining on his contract after expressing his frustration over the financial uncertainty at the club.
The SPL's Doncaster would not be drawn on what sanctions could be imposed – whether a fine, points deduction or transfer embargo. He added: "I'm not going to speculate on what might ultimately be the outcome in the event that any of those orders are not met in full.
"We've been extremely clear today about what we expect to be paid and by when and we'll be monitoring the situation closely to see if those orders are met in full or not."
Meanwhile, Georgios Samaras has called on his Celtic team-mates to guard against complacency following their 10-match winning run to take over pole position in the SPL title race.
Celtic defeated their title rivals Rangers in the Old Firm derby last week and on Monday won 3-0 at Dunfermline to take a two-point lead at the top of the table.
Neil Lennon's men, who on Sunday take a break from league duty when they play at Third Division Peterhead in the Scottish Cup, had trailed Rangers by 15 points at one stage.
Samaras has challenged his team-mates to continue their fine form, saying: "So many people were saying the league was over – they thought 15 points was too big a gap to pull back. But we put in some great performances, won some important games and have now won 10 in a row.
"The important thing now is to build on this. We can't sit back and get complacent – we've done the hard part of closing the gap, but keeping up our form will be even harder.
"We have to win all of our games and January will be a very important month for us."
The 1-0 defeat of Rangers at Parkhead last week was a huge lift, he added: "It was a massive confidence boost beating Rangers, more so than any other club in the league. Everyone in the dressing room felt good about it. We all felt good about ourselves and each other and it was a massive lift for everyone."
Celtic last dropped points in the SPL in October against Hibernian and Samaras added: "I couldn't pick out one game that turned things around for us but if you look back to the game we drew 0-0 with Hibs, we were all very low after that.
"But only a few days later we played in Europe and beat Rennes at home. Then we went away to Motherwell and that was a massive game for us because they were challenging our position in the table.
"We beat them, and that gave us a lot of confidence. And a few weeks later we beat St Mirren 5-0 at home – that was a really good afternoon. We had just started a run at that time and that pushed us on and helped us a lot.
"There were a few big results for us around that time, and even though I didn't play against Kilmarnock, coming back from 3-0 to get a point (on 15 October) helped the guys who played. Their confidence grew.
"We don't want to be in that position again, though, and hopefully now we will continue this form and not look back."
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