What must players do before starting each game in a match?

Before starting each game in a match, players must adhere to several specific actions outlined in the tournament rules. Each of these actions serves to maintain fairness and the integrity of the game.

First, players shuffle their opponent's deck to ensure randomness and prevent any potential manipulation or predictability from the previous game. This promotes an equal starting point for both players and is an essential part of tournament play.

Second, players are required to pass their sideboard cards to their opponent. This allows both players to see the additional cards that have been prepared for potential adjustments after each game. It ensures transparency in how players can modify their strategies in response to the previous game’s outcomes.

Lastly, resolving the winner of the previous game is crucial. It confirms which player has won, as this affects the subsequent game's procedures, including who plays first and any strategic adjustments that may arise from the outcome.

These actions combined ensure a standardized process for starting a new game in a match, thus upholding the rules and fairness expected in competitive play. Consequently, the need for all players to perform these steps reinforces the structure and sportsmanship of Magic: The Gathering.