There was around 25,000 in the middle on a board reading with heads-up action between the big blind and Nazar Buhaiov, who was in early position. The big blind had checked and was in the tank, facing an all-in bet from Buhaiov for around 36,000. He thought for a good while and then decided to make the call.
Buhaiov earned a call from top pair with a gutshot straight draw against his top pair, top kicker, and needed to fade the remaining fives and sixes in the deck to double. The river was safe for him and the appropriate chips were sent his way.