What happens if both players choose the same battlefield during setup in a 1v1 constructed game?

Ruling: Both players are allowed to select the same battlefield during setup in a 1v1 game. There is no rule prohibiting this.

Nuances:

• Each player must have 3 unique battlefields within their own deck (no duplicates among your own 3 battlefields)
• In 2v2 format, teammates cannot use the same battlefields across both of their decks
• The rules do not explicitly specify what happens mechanically when both players select the same battlefield (whether one or two copies enter play), creating a potential gap requiring judge clarification