Ivan Demidov, a 27-year-old Russian, and Peter Eastgate, a 22-year-old from Denmark, will play heads-up for the 2008 World Series of Poker main event championship Monday night at the Rio. They were the last two standing from the 6,844 players who started the tournament when it began in July, and from the nine who reconvened Sunday for the final table after a 117-day break.