Question: Where is the men's professional club basketball based on in which Gustavo Nicolás Aguirre currently plays?

Context paragraphs:
EuroCup Basketball Coach of the Year: The EuroCup Basketball Coach of the Year is an annual award of EuroCup Basketball, which is the secondary level European-wide professional club basketball league, that is given to the player that EuroCup Basketball deems its "top rising star".  The EuroCup Basketball League is the European-wide professional basketball league that is one tier level below the top-tier EuroLeague.  The award began in the EuroCup Basketball 2008–09 season.

San Lorenzo de Almagro (basketball): San Lorenzo de Almagro is the men's professional club basketball section of the San Lorenzo de Almagro multi sports club, that is based in Buenos Aires, Argentina.  The team plays in the Liga Nacional de Básquet (LNB), which is the first tier level division of the Argentine basketball league system.  The team is currently coached by Julio Lamas.  San Lorenzo plays its home games at the Polideportivo Roberto Pando, which is located in Boedo, Buenos Aires.

Polish Basketball Supercup: The Polish Basketball Supercup (Polish: "Superpuchar Polski w Koszykówce") is the supercup game of Polish men's professional club basketball.  Each season, the winner of the Polish League, plays against the winner of the Polish Cup, to cap off the new season.  The first Polish Supercup game was played on September 4, 1999, and it was won by Śląsk Wrocław.

Russian Professional Basketball Championship: The Russian Professional Basketball Championship is the top-tier level men's professional club basketball competition in the country of Russia.  Over the years, there have been 3 different incarnations of the Russian Basketball Championship.  The Russian Super League 1, from the 1991–92 to 2009–10 seasons, the Russian Professional League (PBL), from the 2010–11 to 2011–13 seasons, and the VTB United League, from the 2013–14 season to the present.

European professional club basketball system: The European professional club basketball system or European professional club basketball pyramid is a series of interconnected competitions for professional basketball clubs in Europe.  The system has a hierarchical format with a promotion and demotion system between competitions at different levels.

Basketball Champions League MVP: The Basketball Champions League MVP, or Basketball Champions League MVP of the Season, is the annual award bestowed to the player that is deemed to be the "Most Valuable Player" during the full season of the Basketball Champions League (BCL).  The Basketball Champions League is the third-tier level European-wide men's professional club basketball league in Europe.  The award is given by FIBA.  The award has existed since the Basketball Champions's League inaugural season 2016–17 season.

VTB United League: VTB United League (Russian: Единая Лига ВТБ ) is an international professional men's basketball league that was founded in 2008.  Since 2013, it is the first tier of Russian professional club basketball, as well as the national domestic league of Russia.  Therefore, the highest placed Russian team in the league is also named Russian national champions.  Its goal is to unite the leading basketball clubs of Eastern Europe and Northern Europe together into one league.  The league is sponsored by VTB Bank.  VTB United League averaged 1662 spectators in season 2015/16, down from 2036 in 2014/15.

FIBA EuroChallenge: FIBA EuroChallenge (called the FIBA Europe League in 2003–05, and FIBA EuroCup in 2005–08) was the 3rd tier level transnational men's professional club basketball competition in Europe.  It was organized and run by FIBA Europe.  It is not to be confused with the FIBA EuroCup Challenge – the now defunct 4th tier level transnational men's professional club basketball competition in Europe, which was also organized and run by FIBA Europe, and played during the 2002–03 to 2006–07 seasons.  In 2015, FIBA dissolved the EuroChallenge to start a new second-tier competition, the FIBA Europe Cup, to compete with the EuroCup.

Nicolás Aguirre: Gustavo Nicolás Aguirre (born March 31, 1988) is an Argentine professional basketball player.  He currently plays for San Lorenzo of the Liga Nacional de Básquet.

EuroCup Basketball Rising Star: The EuroCup Basketball Rising Star is an annual award of EuroCup Basketball, which is the secondary level European-wide professional club basketball league, that is given to the player that EuroCup Basketball deems its "top rising star".  The EuroCup Basketball League is the European-wide professional basketball league that is one tier level below the top-tier EuroLeague.  The award began in the EuroCup Basketball 2008–09 season.

Supporting paragraphs: Nicolás Aguirre San Lorenzo de Almagro (basketball)
Answer: Buenos Aires, Argentina