Four days left and it was enough to eliminate about half of the competition in the World Series of Poker's main event. Sometime early Thursday morning, between 1,800 and 2,000 poker players will be left in the running for the top prize of $9.12 million.

All in all 6,844 players entered the $10,000 buy-in No Limit World Championship at the Rio on Thursday. By the time play ended Sunday, 3,663 players remained.

The field will be cut to the final table of nine players early Tuesday morning. Those players will return to the Rio in November to determine the champion.

After a day off Monday, players who survived the opening round of play returned to the Rio for two more days of elimination.

Among the competitors left was 2007 champion Jerry Yang, but 1998 champion Scotty Nguyen busted out.

Nguyen managed to collect nearly $2 million a week ago for winning the $50,000 buy-in H.O.R.S.E. world championship. Yang, who won $8.25 million a year ago in beating a field of 6,358 players, survived play Sunday and will return to the tournament today.

Several other former world poker champions are still alive in the tournament, including Johnny Chan (1987 and 1988) and Phil Hellmuth (1989), who between them have won 21 World Series of Poker titles

Other former champions still in the running are Brad Dougherty (1991), Carlos Mortensen (2001), Chris Moneymaker (2003), and Joe Hachem (2005). Robert Varkonyi, who won the main event in 2002, survived the opening days but was eliminated Tuesday afternoon.

Other notable poker professionals still playing include Phil Gordon, Steve Dannemann, Jennifer Harman, Erik Seidel, Howard Lederer, David Singer, Mike Matusow, Sammy Farha, Rhett Butler and Allen Cunningham. Russian poker player Nikolay Evdakov, who set a record at this year's World Series of Poker for the most times finishing in the money in a single year with 10, survived his opening round and will play Wednesday. Evdakov has won more than $210,000 at this year's tournament, with his highest finish being 12th place in the tournament's first event.