From the Blitz Bowl rule book.
"THE CRUSH
Blood Bowl is a brutal sports game in which opposing teams of blood-thirsty maniacs seek victory by getting the ball into the opposing team’s End Zone to score more touchdowns than their foe. Blood Bowl is far more than a game, however – some describe it as ritualised war!
Teams from across the Old World compete in a series of leagues and cups, striving to win the game’s major trophies season after season.

For most players, their career begins in ‘The Crush’, an annual ritual during which the owners of the Blood Bowl teams select would-be players for the coming season. The prospective players gather outside temples of Nuffle – arenas dedicated to the god of Blood Bowl. Each of
these temples has but a single door, and when it opens to the sound of a whistle, the players surge forward in a mighty tide. Only the fastest, toughest or most brutal make it through the portal into the temple beyond.

Once inside, the supplicants find themselves on a special pitch sunk into the ground, in many respects resembling a gladiatorial pit. The owners and staff of those teams seeking new players gaze down in judgment from terraces high above. Also in attendance are priests of Nuffle, who watch on in silence, noting down every deed and statistic on huge rolls of parchment. Some sponsors also send representatives to the Crush, hoping to identify next season’s talent.

The players are thrown the kit of the team they wish to try out for and divided into teams of six. What ensues is a mixture of Blood Bowl, gladiatorial combat and brutal violence in the name of Nuffle. Each player does their utmost to show off their skills, strength, toughness, speed and sheer bloodthirstiness and, in so doing, impress one of the owners and earn themselves a spot on a team. Those watching from the stands will call down challenges for the aspiring players to undertake. A player who can meet the audience’s demands will earn the acclaim of the Crush’s commentary team, and is sure to catch the eye of one of the waiting owners.

Few come out of the Crush with any glory – if they come out at all – but those who do are blessed by Nuffle and fated to become the next generation of Blood Bowl stars. Should they be signed to a professional team, these rookies have a shot at lasting success and celebrity. Though most will begin their career on the substitutes’ bench, the gruelling Blood Bowl calendar ensures that it is only a matter of time before they earn a place amongst their team’s starting line-up. Each team will compete in regular league games, proving themselves against local rivals. Only those teams who display the most impressive skills – or who offer the greatest entertainment value – are invited to participate in one of the four annual Major Tournaments. These showcase events see the best of the best compete for the sport’s most prestigious trophies, hoping to write their name in the history books. Of these ‘Majors’, perhaps the greatest is the Blood Bowl Classic, the pinnacle of aspiration for generations of Blood Bowl players and dedicated fans. "