Piñeiro was born in Auburn, California, United States to parents of Puerto Rican descent.

And won MVP on Master Tournament at Turabo Heights[3] Piñeiro began his collegiate career with Sierra College, where he averaged 15.4 points and 7.4 rebounds per game as a freshman.

[3] He then transferred to Portland State, where he played all 31 games in his sophomore season averaging 12.0 points and 5.5 rebounds, while shooting 50.7 from the field and 76.3 from the free throw line.

In his redshirt junior year, Piñeiro earned First-team All-WCC honors as he led the team in scoring (15.7 ppg) and rebounding (6.2 rpg), while averaging 49.1 from the field and 78.3 from the free throw line.

[6] On July 30, 2019, Piñeiro signed with the Sacramento Kings, a reported one-year partially guaranteed contract.