In Round 6 of Grand Prix Prague, Magic Pro League member Rei Sato was disqualified.
Head Judge Emilien Wild explained the situation that led to this decision as follows: "Sato was planning what was going to be his last attack of the current game. He went to declare attackers and then noticed that he forgot to play his land for the turn, a land that he needed for his attack to work out. He didn't acknowledge this fact and didn't ask for permission to back up to his main phase, but instead he just placed the land onto the battlefield and finished declaring his attackers.
"During our investigation, we determined that Sato was aware that what he did was against the rules. Thus, he was disqualified from the event."
This infraction will be further investigated by the MPL, according to Wizards of the Coast representatives.