Tyrone have been hit by the inter-county retirements of former Footballer of the Year Stephen O'Neill and Martin Penrose, BBC Sport understands.
O'Neill, 33, won three All-Ireland titles in a stellar career which also saw him pick up three All Stars awards.
The Clann na nGael forward, who made a comeback after retiring in 2008, has struggled recently with injuries.
Penrose enjoyed All-Ireland triumphs with Tyrone in 2005 and 2008 to go with three Ulster titles.
The Carrickmore forward also won the Dr McKenna Cup four times under manager Mickey Harte.
O'Neill was a key player for Harte's team in a golden era for Tyrone and he won an All-Star in 2001, two years before winning the first of three All-Sam Maguire successes in five years.
The 2005 season brought not just team glory for O'Neill, for he went on become Footballer of the Year.
O'Neill announced his retirement in January 2008 but he returned for the All-Ireland final, although he refused to receive his medal as he said he "did not earn" it.
He won his final All Star award a year later before suffering a string of injuries, including dislocating an elbow in the 2010 McKenna Cup final.
Tyrone were knocked out of the All-Ireland qualifiers by Ulster rivals Armagh at Healy Park in July.