Matt Stout -- a 12-year poker pro with over $1.4 million in WSOP earnings -- got his butt kicked once by the passenger who was savagely yanked off the United Airlines flight.
Stout tells TMZ he was in a poker tourney with Dr. David Dao in 2009, and both made the final table ... but Dao got there with a crazy, fearless style. Stout says he lost most of his chips to Dao when they were down to 3 players at the table ... which kept Stout from winning the tourney.
Dao finished second and won more than $117k.
Stout remembers Dao as a quiet guy who kept to himself -- despite his maverick style of playing -- which made the video of the United Airlines incident way more shocking to him.