Martynas Mažeika is a Lithuanian professional basketball executive and former player. At 1.93 m in height, he played as point guard and shooting guard, preferring the latter position. He is currently the general manager for Neptūnas Klaipėda.

Basketball Club Neptūnas, commonly known as Neptūnas or Neptūnas Klaipėda, is a Lithuanian professional basketball club based in Klaipėda, Lithuania. The club participates in the Lithuanian Basketball League. It was founded in 1962 under the name BC Maistas and in 1964, BC Maistas's name was changed to BC Neptūnas. The club carries the name of the Roman sea god Neptune. Neptūnas participated in the 2014–15 EuroLeague season and is only the third Lithuanian club to participate in the premier European basketball league, after Žalgiris and Rytas.