The opening week of the football championship threw up a number of surprise results across the country.

Division Four side Wicklow beat Division Three champions Westmeath in Leinster. Waterford turned over Tipperary in Munster - their first win in the province since 2010. And in Ulster Cavan surprised Monaghan in Clones.

Fermanagh manager, Kieran Donnelly, will be hoping his side can cause another upset when they welcome Armagh to Brewster Park on Sunday.

But he knows it will be a huge challenge.

"We are expecting a massive challenge from Armagh," the Fermanagh manager said.

"They prob should be Ulster champions from last year. They were extremely unlucky against Derry so we are very aware.

"They have massive strength in depth and predicting the team in itself from Armagh is going to be the hardest part because they have so many players returning from injury.

"We know it is a big challenge but it is one you are always going to face in Ulster no matter who you play, but it's one our boys will look forward to."

Armagh won in Brewster Park during the league and ultimately went on to gain promotion. For Fermanagh it was the opposite way and relegation.

But Donnelly does not dwell too long on the past. He and his management team will have looked at the games but as the results showed from last weekend nothing is impossible when it comes to Championship football.

"As a manager, I have stopped reading into any past games or past sessions because the game takes a life in itself.

"From this weekend in itself you can see the way Cavan went and beat Monaghan, Wicklow went and beat Westmeath who were on a high after beating Down.

"There is no science to it, it's all key moments on the game day that make the difference and how you react to them and who gets that score at the key time or refereeing decision.

"And all you can do is prepare as well as you can going into the championship game and that's all we are focussing on. Making sure training is good, our attitude is good and see where that takes us."

Fermanagh's hand will have been strengthened by the return to play of Johnny Cassidy and Darragh McGurn. However, goalkeeper, Sean McNally and forward Ryan Lyons are still unavailable through injury.

Cassidy and McGurn have been working back up to fitness from their respective injuries and while they may not start on Sunday, having them back in training and pushing for selection can only be a good thing for Fermanagh's preparation.

"The likes of Johnny and Darragh are all pushing hard which has added strength to training and depth to the squad as well, and also competition.

"And if we intend to have a long summer we're going to need everybody within the squad to be fit.

"They are both quality players and they do add to training.

"It means the competition is strong. Going into it we would be happy with where we are at in terms of options and there are certain players that are training really well at training that have missed out on league games with wee niggles and injuries," said Donnelly who admitted this is probably the strongest squad he has to pick from this year.

The Brookeborough native is expecting Armagh to come with high intensity, physical game on Sunday. They did it at times in the league encounter and put Fermanagh under serious pressure and should have scored two goals.

Armagh are favourites to take the spoils again in Brewster Park but Donnelly said the mindset in the camp is one of positivity.

"We have to take as much positivity as we can going into this game. There is belief within our squad but we know we have to perform.

"The Armagh team probably don't get the credit they deserve either and I do rate Kieran McGeeney very highly as a manager, the way he has kept that squad together and the way he has developed the squad.

"We are under no illusions that it’s a tough task but we are confident within ourselves.

"We know if we perform to the level we know we can then we'll always be a tough team to beat in Brewster.

"And we hope to bring that energy and commitment and collective focus into the game on Sunday," concluded the Fermanagh boss.