Last Aggressor
Masa Kagawa opened to 4,000 on the button, Jason Mercier defended his big blind, and the flop came down . Mercier checked, Kagawa continued for 5,500, and Mercier called.
The turn was the suicide king (), and both players checked. The on the river completed the board, and both players checked again, but nobody turned their cards over.
"You show first," Mercier blurted.
Kagawa flashed a card, which we unfortunately missed, and mucked his hand. Mercier turned over for ace-high, and won the pot. After the hand, a floor person was called over and asked who has to show first: the last aggressor or the player out of position? The floor person confirmed Mercier's statement, saying that the first player to show is the last aggressor.
Now we know, and knowing is half the battle.