After discussion following the success of the return of best-of-five matches for Sunday playoffs at Pro Tours, we have decided to make a change to how sideboarding functions in best-of-five matches played on Sunday at Pro Tours and the Magic: The Gathering World Championship.
Starting with Pro Tour Shadows over Innistrad in Madrid, Spain, the first two games played in a best-of-five playoff match on Sunday will be pre-sideboard games. After Game 2 is completed, players may change cards in and out from their sideboards and main decks in between games.