Declan Bonner has made three changes to the Donegal team that drew with Kerry two weeks ago.
Paddy McGrath, Neil McGee and Daire O’Baoil have come into the team to face Mayo at Castlebar.
A draw would be enough for the Tir Chonaill county, while only a win will do for the Westeners to book a semi-final spot.
James Horan has also made three changes to his team from the last day.
The action gets underway at 6pm.
At the same time in Navan, Kerry take on Meath.
Like Donegal, Kerry only need a draw to get into the last-four, while Meath have already been eliminated.
Cork are All-Ireland under-20 football champions.
The Rebels came back from being nine points down in the early stages to beat Dublin in Portlaoise by 3-16 to 1-14.
Three goals in quick succession was the turning point for Cork as they led for much of the second half.
It’s the first time they’ve won the competition since 2009, and the first in the new under-20 format.
Cork are into the All-Ireland under-20 hurling final.
They beat Kilkenny in Portlaoise on a scoreline of 1-16 to 13 points.
Cork have booked their place in the last-four of the All-Ireland Ladies Football Championship.
They beat Tyrone comprehensively by 7-18 to 3-04.
Later, Semple Stadium hosts a quarter-final double header in the Liberty Insurance All-Ireland Camogie championship.
Limerick and Tipperary get underway at 5.30, then at 7.15, Galway face Waterford.
Cyclist Chris Froome says he could barely breathe and was coughing up blood after surgery on the injuries that ended his 2019 season.
He suffered a fracture to his neck and right leg, as well as breaking a hip and multiple bones during a practice ride in June.
Froome says his recovery is ahead of schedule.
Celtic have got the defence of their Scottish Premiership crown off to the best possible start.
They beat St Johnstone 7-0 at Parkhead.
Ryan Christie got a hat-trick, while Odsonn Edouard and Leigh Griffiths also got on the scoresheet.
There’s one game in the SSE Airtricity First Division this evening.
Shelbourne will look to extend their advantage at the top of the table to eight points with victory over Cobh Ramblers.
The action in Cork gets underway at 7pm.
Celtic have started off the defence of their Scottish Premiership title with a thumping win over St Johnstone.
Ryan Christie scored a hat-trick as the champions triumphed 7-nil at Parkhead.
Ross County began their top flight campaign with a 3-nil victory against Hamilton.
Hibs beat St Mirren 1-nil – while Livingston against Motherwell finished goalless.
Franny Kiernan reports
It’s day 6 of the 150th Galway Festival.
One Cool Poet is looking to make a little piece of Galway history by winning for the third time this week, he runs at 5.20.
While, the feature at Glorious Goodwood, the Lillie Langtry Stakes was won by the John Gosden trained Enbihaar.
Australia are back at the crease after bowling out England in the first Ashes test for 374 runs.
A short time ago at Edgbaston, the visitors were 64 for 2, trailing by 26.