CASI

Rafael Cullen took over the rugby section in 1916 and did more than rebuild it: he put his players in black-and-white hoops copied from the British Barbarians. San Isidro's football club, the older half of the story, had already been playing since a 1902 merger of two local sides, and it stayed in the Argentine Primera División until 1931, taking the Tie Cup in 1912 before the club walked away from professional football rather than follow the game down that road.

Rugby is what stuck, and what earned CASI the nickname La Academia — a name given not for the trophies alone. The tally backs it up: 33 championships, more than any other club in the competition's history, running from 1917 to 2005. The 1935 season split the club rather than simply testing it — eleven players, suspended after an incident following a match, left to found a rival across town rather than serve out the ban.

That rival was San Isidro Club, and the two have shared a fixture, the Clásico Sanisidrense, ever since. The 2005 final between them carried more than local pride: CASI had gone twenty years without the title, and beat SIC 18-17 to end the drought at the ground the players call La Catedral del Rugby, whose 3,000-seat concrete stand swells to roughly 4,500 for occasions exactly like that one. The clásico remains the fixture by which a CASI season is still judged, whatever else the year has held.