Every year a football match is held between the teams of Earth and Mars. For the last sixty-seven years, victory has gone to the team of the red planet, of which forty-two years in a row have been dry - this is because the earthlings have become too pampered and soft-bodied. All the tough guys work in the Martian mines and forests of Venus. This is who should be taught the game... But there is also rule 18, which states that only athletes who have not had the slightest admixture of alien blood in the blood of their ancestors for at least ten generations can be allowed to play. However, the coach of the earthly team, Snelling, came up with how to assemble a team capable of defeating the Martians without violating Rule 18...(full text of the story)