[1] Gonzalito was born into a family of polo players and is the eldest son of polo legend Gonzalo Pieres Sn and his wife Cecilia Rodríguez Piola.

After losing the Argentine Open finals in 2005 and 2007 in extra-time only, his team Ellerstina was considered a strong rival for the La Dolfina Polo Team and in 2008 met the expectations by beating La Dolfina 13-12 through a golden goal in an extra-chukka, which was made by Gonzalo.

[2] Other teams Gonzalo played for include Audi, Loro Piana, Outback, Ellerston, Tonkawa, and Black Watch.

He has won tournaments in Sotogrande (Spain), Deauville (France) and England.

In 2008, he won the Abierto Argentino de Polo with Ellerstina Etiqueta Negra and the Queen's Cup with Ellerston for the first time.