Ospreys' Wales stars will have the chance to play at the Millennium Stadium for the fifth and sixth times this year if they beat Saracens in Sunday's European Cup quarter-final.
The likes of Ryan Jones, Gavin Henson and Shane Williams played in all three of Wales' home RBS 6 Nations matches.
They returned to the Millennium Stadium a week after securing the Grand Slam against France when they hammered Sunday's opponents 30-3 to reach the final of the Anglo-Welsh Cup to be held at Twickenham.
Should Ospreys repeat that result they will face either Munster or Gloucester in Cardiff on April 26 or 27 with the final to be played at the same venue on May 24.
If Saracens prevail at Vicarage Road on Sunday, their semi-final will be played at Coventry's Ricoh Arena.
Cardiff Blues, the other Welsh side still in the European Cup, travel to France to face Toulouse on Sunday.
Their potential semi-final final venue depends on the outcome of London Irish versus Perpignan on Saturday.
The Blues will face Irish at Twickenham or Perpignan at the Stade de la Mosson in Montpellier.
England flanker James Haskell insists he will be pushing as hard as possible to be back from a toe injury in time to make his case for a spot in Eddie Jones' side looking to defend their RBS 6 Nations title next year.