Mayo have been dealt an injury blow after Evan Regan broke his collarbone for the second time this year during training on Tuesday.
The Ballina Stephenites player suffered the same injury in an Allianz Football League match against Kerry in February.
It will rule Regan out for at least 12 weeks, which includes the entire Connacht Football Championship.
A statement from Mayo GAA read: "Evan has been to visit the consultant and in conjunction with the Mayo Senior Football Medical Team will be reviewed and will continue to work to get Evan back to full fitness as soon as is possible.
"We wish Evan a speedy recovery and look forward to seeing him back on the playing field in the Green & Red soon."
Mayo begin their Championship with a semi-final against New York, Galway or Leitrim.
