A calm and composed defender who started his youth career with Athletic Bilbao, Onaindia has now spent more than a decade playing for various clubs across the Spanish leagues. He caught the eye playing for Mirandes in the last couple of seasons after he helped the club clinch promotion to La Liga 2 in 2019. The Lekeitio-born defender played a key role in their run to the Copa Del Rey semi-final beating the likes of Celta de Vigo, Sevilla FC and Villareal. He started every game for Hyderabad FC in his debut ISL campaign, and was one of the most consistent defenders in the league, playing a crucial role in the club’s push to a place in the play-offs in the 2020-21 season. He returned to Mirandes for the 2021-22 season, where he was the captain of the side that finished 14th in the league. But Odei decided to come back to the Indian Super League and penned a deal with Hyderabad FC for the upcoming campaign.