Donegal captain Paddy McBrearty is set to miss some crunch League games due to a hamstring injury sustained against Tyrone.
McBrearty kicked the winning point as Donegal opened the League campaign with a win over All-Ireland champions Kerry last month but he was withdrawn as they were well beaten in Omagh last time out.
They face bottom-of-the-table Monaghan in Clones on Sunday followed by Galway and Armagh in the two subsequent weekends in games that could define their League campaign.
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With talisman Michael Murphy having retired in November, Donegal boss Paddy Carr can ill-afford to lose another experienced member of his attack for a sustained period.
"He is being looked after by the medical people but at the moment it is highly unlikely that he will be available for Sunday unfortunately," Donegal manager Paddy Carr told Donegal Live.
"He is the only one that went off with an injury. There are a few others that had knocks and bruises but they should be pretty much available for selection.”
Carr is already without the likes of Eoghan Ban Gallagher, Ryan McHugh and Michael Langan and defeat to Monaghan could see Donegal dragged into a relegation battle.
"Monaghan have a very proud record in terms of their survivability and their resilience. They have been in Division One for quite a while now and it's a credit to them," added Carr.
"Everyone knows the consistency and value of competing against the best teams and essentially that should be an advantage going into Championship; maybe not always in Ulster as teams have won from Division Two and recently Division Three.
"But everyone knows that you learn so much more from playing the very best.
"That's why we took a fair few learning points from the game against Tyrone. There were a good few young lads who played that day who hadn't featured in anything like that before. They should, I do believe, be the better for it.”
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