Proving on paper that poker is primarily a game of skill, not luck, is trickier than it sounds, as University of Denver professor Robert Hannum explains in this week's feature "All In." But fans of the World Series of Poker see that thesis in action on the tube every time one of the big dogs executes a masterful bluff, buying a big pot with weak cards, or avoids hidden but certain disaster with a monster laydown.

Here are three memorable moments from the WSOP of heads-up, final table play that show the skill aspects of the game at their finest.

1. Johnny Chan vs. Eric Seidel, 1988

The legendary Chan won back-to-back championships in the late 1980s, and this hand is a pretty good demonstration of how he did it. He owns the table from the flop, but look how he reels Seidel in with well-feigned hesitation. Matt Damon reviews the scene (and comes close to reliving it in his own showdown with John Malkovich) in the movie Rounders, one of our top 10 gambling movies of all time.

2. Scotty Nguyen vs. Kevin McBride, 1998

An ominous hand played to perfection by Nguyen, right down to the beer, the Elvis shades and the famous sneer, "You call, and it's going to be all over, baby!" The board is a full house; Nguyen starts with trip nines, and it only gets better. Figuring Nguyen's oddball behavior is all front, McBride calls. And it's all over, baby.

3. Chris Moneymaker vs. Sam Farha, 2003

This showdown between an established pro and an upstart who clawed his way to the Main Event from a satellite tournament is a watershed event, one that gave the WSOP an exponential boost in popularity. And in this key hand, a star is born, as Moneymaker buys a big pot with cards straight out of the garbage can.

More from our Follow That Story archive: "Poker skills quiz: Test your savvy against DU expert Robert Hannum -- and no bluffing!"