Mayo's chances of beating All-Ireland champions Dublin for the first time since 2012 have received a big blow after two more key defenders picked up injuries.

All Star defender Brendan Harrison is rated as ‘a major doubt’ for Saturday night’s Allianz Football League Division 1 game in Castlebar due to a hip problem while half-back Paddy Durcan is considered ‘doubtful’ due to a leg injury.

Mayo have lost to the Dubs in the last two All-Ireland finals, pushing the 2016 decider to a replay, and they haven't beaten the Boys in Blue since the semi-final stage six years ago.

Manager Stephen Rochford was without eight of the team that started last year’s All-Ireland final defeat to the Dubs for Mayo’s recent league loss to Galway.

He is already resigned to being without All Stars Chris Barrett and Keith Higgins, along with Donie Vaughan for Mayo’s upcoming games.

Last year’s captain Cillian O’Connor is also suspended for next weekend’s match after being red-carded against Galway.

On a more positive note, Lee Keegan is understood to be making excellent progress since returning to training after surgical procedures on both of his hips last November.

But the 2016 Footballer of the Year will not be ready to return to competitive action until next month.

Higgins, meanwhile, is currently on an extended break from the football squad and is instead lining out with the Mayo hurlers in Division 2B of the National League.

The four-time All Star defender scored five points for the hurlers from full-forward against Derry at Celtic Park last Sunday.

Tom Parsons tackles Dublin's Michael Darragh Macauley

It also remains to be seen whether first-choice midfielders Tom Parsons or Seamie O’Shea will return to Mayo’s match-day squad next weekend.

Neither of them have played yet this year, with Parsons out of the country on his honeymoon and O’Shea sidelined with a knee injury.

However, current Footballer of the Year Andy Moran will be available for selection against Dublin after missing the defeat to Galway due to a family bereavement.

A number of players were released from Mayo’s extended panel recently, including experienced defender Kevin Keane and 2016 All-Ireland under-21 winners Brian Reape and Michael Plunkett.