SAINTS' away game at Huddersfield Giants scheduled for Monday 29 May has been moved to Friday 16 June with an 8pm kick off.
The game was initially part of a weekend double header, but Huddersfield Town will be in the Championship play offs at Wembley that day.
If Huddersfield beat Reading they will be in the top flight for the first time since the early 70s.
As both teams are already out of the Challenge Cup, the match has been slotted in for that blank date.
Giants Managing Director Richard Thewlis said: "Since Huddersfield Town's magnificent victory we have been inundated with calls from supporters wanting to share the Wembley experience as well as a huge number of stadium staff here which made the actual staging of our game extremely problematical.
"It's fully expected that 40,000 Huddersfield sports fans will descend on London that day to hopefully see a Town win and with both ourselves and the Saints having a free weekend later in the year the move made a lot of sense to us both.
"It helps logistically as I say with the stadium safety team, stewards, car parks, turnstile operators and caterers - the vast majority of whom want to be at Wembley which they are now able to do.
"From a playing perspective both sides avoid the two games in four days scenario which no one likes whilst accepting that there now is no week break in June as had been anticipated."