Question: What river is the namesake of the city that sports club Boca Río Gallegos is located in?

Context articles: Veintiocho de Noviembre
National University of Austral Patagonia
Boca Juniors (women)
Juan Manuel Cortés
Atlético Boxing Club
Roman Catholic Diocese of Río Gallegos
Gallegos River
Boca Río Gallegos
Matanza River
Río Gallegos, Santa Cruz

28 de Noviembre, written out as Veintiocho de Noviembre, is a town in southwestern Santa Cruz Province, Argentina.
 It has roughly 5,300 inhabitants, most of whom are of Argentinian and Italian origin, and is located 270 km west of Río Gallegos and 13 km south of Río Turbio.
 The town is near the border with Chile, not far from Puerto Natales.
 Its main economic activity is coal mining.
The National University of Austral Patagonia (Spanish: "Universidad Nacional de la Patagonia Austral" ) is an Argentine national university in Santa Cruz Province.
 The university is divided into four campuses, located in the cities of Caleta Olivia (UACO), Río Gallegos (UARG), San Julián (UASJ) and Río Turbio (UART), and was founded in 1995, by national law 24.446.
Boca Juniors Femenino is the women's football team of Argentine sports club Boca Juniors.
 Established in 1990, it has been the leading force in the Argentinian Championship since the late 1990s, having won 21 of the 33 editions of the competition as of May 2013, including a five-years streak winning both the Apertura and Clausura championships.
Juan Manuel Cortés (born November 20, 1980 in Quilmes (Buenos Aires), Argentina) is an Argentine footballer currently playing for Boca Río Gallegos in Torneo Argentino B.
Atlético Boxing Club is an Argentine football club located in the city of Río Gallegos, Santa Cruz.
 The team currently plays in Torneo Federal B, the regionalised fourth division of the Argentine football league system.
The Roman Catholic Diocese of Río Gallegos is located in the city of Río Gallegos, the capital of the Patagonia province of Santa Cruz, Argentina.
The Gallegos River (Spanish: Río Gallegos ) is a river in the Argentine province of Santa Cruz, on whose estuary lies Río Gallegos city, capital of the province.
Club Boca Río Gallegos is an Argentine sports club from the city of Río Gallegos, Santa Cruz.
 Although other sports are practised (such as basketball, field hockey or taekwondo), the club is mostly known for its football team, which currently plays in the Torneo Argentino B, the regionalised 4th level of Argentine football league system.
The Matanza River is known by several names, including, in Spanish, Río de la Matanza ("the slaughter river" in English), Río Matanza ("slaughter river"), Río Mataderos ("slaughterhouses river"), Río de la Manzana ("the apple river") or simply Riachuelo ("little river" or "brook").
 It is a 64 km stream in Argentina that originates in the Buenos Aires Province and defines the southern boundary of the Buenos Aires federal district.
 It empties into the Río de la Plata between Tandanor and Dock Sud.
 The La Boca neighbourhood and the Boca Juniors football club are located near the Riachuelo's mouth.
 The Spanish word "boca" means "mouth".
Río Gallegos (] ) is the capital and largest settlement of the Patagonian province of Santa Cruz in Argentina.
 Located in the department of Guer Aike, it has a population of about 98,000, according to the 2010 census , a 24% increase from the 79,000 in the 2001 census .
 The city bears the name of the Gallegos River, and sits on its estuary 2636 km south from the Argentinian federal capital Buenos Aires.