[2] Throughout his sporting career, Brin has been training for Team Caltex Boxing Club under his head coach and mentor Nolito Velasco.

[3][4] Brin made his official debut at the 1996 Summer Olympics in Atlanta, where he ousted his opening match to Cuba's Julio González Valladares in men's lightweight division (60 kg), receiving a default score of 13–24.

[5][6] At the 2000 Summer Olympics in Sydney, Brin was upgraded to light welterweight division (63.5 kg), but lost the same round again to Belarus' Siarhei Bykovski in a close decision of 5–8.

[9] Unlike his two previous Games, Brin outclassed Sweden's Patrick Bogere in the opening round with a satisfactory 43–35 triumph, before losing out his next match to Thailand's Manus Boonjumnong in a decisive score of 15–29.

[10][11] Following an official retirement from his third Olympics, Brin is currently working as a national youth coach for the Amateur Boxing Association of the Philippines.