19-month-old Tess seemed to forget which county she's from.
Mayo may have just got that luck they've been waiting for...
The video clip shows Tyrone toddler Tess practicing her support of the Tyrone team, before she suddenly switches her allegiance to Mayo.
The 19-month-old, who also happens to be the cousin of Tyrone Captain Pádraig Hampsey, is seen shouting "c'mon Mayo", surprising mother Caroline in the process.
"No, not Mayo!" Tess' mother shouts while laughing.
Despite numerous attempts to correct the toddler, it looks like there'll be one less Tyrone supporter on Saturday.