One of Argentine football's oldest jokes is two games away from losing validity.
All of the Buenos Aires big five have won the Copa Libertadores, South America's equivalent of the Champions League -- or rather, all of them with the exception of San Lorenzo.
This has allowed rival fans enormous fun with the club's full name, Club Atletico San Lorenzo de Almagro. According to malicious tongues, the initials really stand for Club Atletico Sin (without) Libertadores de America.
Two years ago, the joke seemed sure to last a good many years. San Lorenzo were battling against relegation from the Argentine first division. But they survived, and since one of their staunchest fans, Cardinal Bergoglio, was transformed into Pope Francis, they would seem to have been blessed.
A domestic title has now been followed by qualification for the two-legged final of the 2014 Libertadores.
The hard part was done last week in the first leg of the semifinal. San Lorenzo were at home to Bolivar of Bolivia, one of the most pleasant surprises of a competition full of shocks.
Compact and well organised, Bolivar had put together a nine-game unbeaten run in the competition. Typically, they rely heavily on the extreme altitude of their mountain home in La Paz, 3,600 metres above the Andes. This year, though, their away form had been especially impressive -- until they went to Buenos Aires, where they capitulated on their way to a 5-0 defeat.
San Lorenzo did not even have to work particularly hard to open up such an advantage.
Bolivar effectively committed soccer suicide; three of the goals came from dreadful marking at free kicks, one resulted from a poor defensive clearance -- the other was scored by perhaps the outstanding player of this year's competition.
Veteran San Lorenzo captain Juan Mercier is the symbol of an experienced, unflashy side.
He plays within his limitations, does the simple things well, reads the game outstandingly and comes up big in the key moments. In that first leg against Bolivar, he took a rare opportunity to do something more eye-catching, snapping into a tackle in his own half and seeing the move through with a well-drilled shot from the edge of the area.
With a 5-0 cushion, Mercier and company could travel relieved up the Andes for the second leg.
Coach Edgardo Bauza is well acquainted with altitude; he was in charge of Ecuador's LDU of Quito when they won the Libertadores six years ago. With teenage Hector Villalba (the only player under 24 and one of only three under 29), the team's pacey escape valve, San Lorenzo kept compact, tried to run as little as possible in the rarefied air and concentrated on running the clock down. Bolivar applied some pressure at the start of both halves, but their only goal came in second-half stoppage time.
It did mean that, in keeping with a frequent Libertadores pattern of home advantage, all four semifinal matches were won by the hosts, without the visitors managing a single goal.
The drama that was absent in the San Lorenzo-Bolivar tie was found in abundance in the other matchup, between Nacional of Paraguay and Defensor of Uruguay. These two clubs, traditional but relatively tiny, also were going in search of their first Libertadores title.
A week ago in Asuncion, Nacional won 2-0, a victory which highlighted the dynamic midfield which youthful coach Gustavo Morinigo has assembled. Silvio Torrales and Derlis Orue are full of aggressive running, getting up in support of wide men Marcos Melgarejo and Julian Benitez.
And for the closing stages of the competition, Nacional have managed to draft in Brian Montenegro, a highly promising left-footed centre forward. He opened the scoring, Orue added another from a poorly cleared corner, and Nacional had a handy lead to take to Montevideo.
Defensor, though, could boast a fine home record and the team which has scored most goals in the competition. It is, as befits the current Uruguayan domestic scene, a side made up of promising youngsters and grizzled veterans -- anyone in between of real quality has long been sold.
Captain Andres Fleurquin, 38, dictates operations intelligently from defensive midfield. Ahead of him Nico Olivera, 36, in spasms still shows off the skills that made him the star of the 1997 World Under-20 Cup.
A year ago, Uruguay reached the final of the same competition. One of their best players was playmaker Giorgian De Arrascaeta, with his uncanny ability to receive and give passes while on the turn. A year older, at 21, is the flying Brazilian-born winger Felipe Gedoz. When they all combined, they played some fine football -- but they could pull only one goal back against Nacional.
Defensor hit the post and the bar in the last few minutes, and probably deserved to go through on the balance of play over the two games. But instead it is Nacional of Paraguay who will attempt to ensure that one of Argentina's traditional teams remain Club Atletico Sin Libertadores de America.
Tim Vickery is an English journalist who has been based in Brazil for the past 20 years. He is the South American football correspondent for the BBC Sport.