Hayes, the first choice full- back on the senior team, retired injured in the second-half of the Munster final against Kerry and has lost his fitness battle.
The number three slot goes to Eamonn Walsh, who replaced Hayes in the provincial decider. That is the only change from the history-making side that won the Decies its first Munster title in the grade.
Wing back John Hurney and forwards Mark Power and Bob Costelloe, who were all substituted in the Munster final, retain their places.
Meanwhile, inspirational captain Niall Hennessy of Ardmore has been named in his customary right half back berth despite being forced out of a club game last weekend suffering from concussion.
Team manager Pat Nugent said the heroes who mastered Kerry in the Munster final fully deserved a vote of confidence. Nugent said the injury that rules Ger Hayes out is unfortunate but will increase their resolve even more to keep their giant-killing run going.
County Board chairman Paddy Joe Ryan has also described the loss of Hayes as “monumental” but is confident the team will again rise to the occasion.
“It defies even logic itself that we are in this All-Ireland semi-final but after beating Clare, Cork and Kerry in turn no one can question our right to be there”, the Deise chairman said yesterday.
WATERFORD: D. Hickey (Brickey Rangers); M. Crotty (Rathgormack). E. Walsh (St. Olivers). J. O’Reilly (Tramore); N. Hennessy (Ardmore) capt. E. Rockett (Portlaw). J. Hurney (Ballinacourty); S. Dempsey (Colligan Emmetts). M. Walsh (Stradbally); L. O’Lionain (An Ghaeltacht). M. Power (Tramore). T.Whelan (do); B. Costelloe (do). S. Walsh (Nire). B. Harty (Ardmore).