'Donegal's top three traits can help them reach final'

Just like that, we have a football championship on our hands. Most people would agree that, across the piece, the All-Ireland quarter-finals left much to be desired when it came to edge-of-your-seat thrills.

But Galway's win over Dublin has blown the race for the Sam Maguire wide open and adds more intrigue heading into semi-final weekend.

What we're left with are four teams who will rightly feel they can go all the way. While Kerry prevailed two years ago, the wait for Armagh (22 years), Galway (23 years) and Donegal (12 years) to get their hands back on Sam has been long and torturous.

It'll be great to be back in the BBC studio for Armagh v Kerry on Saturday and Donegal v Galway on Sunday.

Here's how I think they will go.

Kerry need attack to click to break Armagh hearts

Kerry showed Derry a huge amount of respect in the quarter-final.

Derry travelled to Croke Park ready for a war of attrition and Kerry decided to mimic that to avoid being vulnerable to counter-attacks.

Kerry's celebrations at the end struck me. Their fairly muted reaction made it seem like it was job done and not a significant win over an All-Ireland contender.

The way Kerry played was a far cry from the panache and style we've seen from the Kingdom down the years, but I was heartened to hear Jack O'Connor admitting that Kerry's attack lacked spark and energy against Derry. They'll need to sharpen up at that end of the field against Armagh because Kieran McGeeney's side have the ability to stall the green and gold.

Armagh have looked cohesive in defence this year. They have played 15 games in league and championship this year and have kept 14 clean sheets (Cork scored two goals against them in the league).

My fear for Armagh, however, centres on attack and whether they can get enough scores on the board. To beat Kerry, they'll need their forwards firing on all cylinders. Conor Turbitt has played well this year and Oisin Conaty kicked four from play the last day, but he has also been used in a defensive capacity. Rory Grugan and Rian O'Neill have shown flashes this year, but they will need to fire for the entire 70 minutes.

There's no doubt Armagh have the forward unit to trouble Kerry. But with defence often being a priority, they haven't gotten the most out of their forwards at times.

That was evident against Roscommon until Stefan Campbell came on. He's so forward-thinking and offered that sense of urgency going forward, kicking two points and setting up another couple.

I do have a newfound respect for Armagh given how they have rebounded from some heartbreaking defeats, the likes of which would have haunted me for a while as a player.

They are a resilient bunch and their more seasoned campaigners have stuck with them through some dark periods.

That toughness will stand to them this weekend in a semi-final I can see going right down to the wire. But I feel that if Kerry answer O'Connor's call and bring more spark to their attack, they will have just about enough to reach a third final in a row.

Donegal scoring power could be key

Donegal have not had to be overly reliant on captain Patrick McBrearty and Oisin Gallen for scores

After the troubles of last year, a lot of Donegal people didn't expect to be back in an All-Ireland semi-final so soon, but Jim McGuinness' side have been seriously consistent all year.

You would associate consistency with McGuinness' first spell in charge, and while it would be wrong to paint this side in the exact same light, they do share some key traits.

Firstly, they've managed to mostly keep the goals out. Another big plus is how they have kept the opposition's key men out of games. Think back to how they kept Derry's Shane McGuigan, Conor Glass and Brendan Rogers quiet or Tyrone's Darragh Canavan and even Louth's Sam Mulroy in the quarter-final.

That has been a cornerstone of Donegal's success in the past. On top of that, they're amassing big scorelines, averaging around 22 points per game. That'll get the job done for most teams.

They have a marquee forward in Oisin Gallen but they haven't been overly reliant on him or Patrick McBrearty for scores. Against Louth, they had 11 different scorers and we've seen big performances from players all over the pitch. Peadar Mogan has won back-to-back player of the month awards and will be a key outlet again on Sunday.

Scoring heavily, keeping out goals and nullifying key threats. Donegal will bring all three, but beating Dublin gave Galway's challenge a huge shot in the arm.

Galway have been steady this year, and when you think about their road to this point, it's hard not to be impressed. They beat Mayo in a tight Connacht final, faced Armagh and Derry in the group stage and toppled Dublin in the quarter-final.

They're probably the most battle-hardened of the four remaining teams. Their average winning margin is around two points, too, so they have a habit of edging close games.

Galway have the ability to hurt teams with their powerplays in attack, but for me, their chances will hinge on whether or not they can keep their key men on the pitch.

Against Dublin, Damien Comer seemed to be limping at the end, Shane Walsh was forced off and they lost Sean Kelly in the first half. Walsh is a phenomenal forward and the type of scores he can conjure are not easily to replace.

But Galway's strength in depth has helped them this year. Injury woes earlier in the season challenged Padraic Joyce but he adapted well and gave significant game time to a lot of his squad.

In the Dublin game, Joyce brought on Cein Darcy, Liam O Conghaile, Johnny Heaney, Cian Hernon and Tomo Culhane, all of whom have a lot of minutes in their legs - and that makes a difference.

They're also a big side in the middle of the field. John Maher, Cillian McDaid and Paul Conroy are all at least 6ft 2ins. Jason McGee didn't play against Louth but Donegal will need him back to combat Galway's aerial presence.

Galway were able to field their strongest 15 against Dublin. They play with lovely variety and balance, but I'm backing Donegal to draw on the qualities that have gotten them to this stage and make the county's first All-Ireland final in 10 years.

Michael Murphy was speaking to BBC Sport NI's Matt Gault