A midfielder, Vanags made his debut with Universitātes Sports before moving to ASK Rīga. He scored 9 goals for Latvia in 18 matches (from 1937 to 1939). In addition to football Vanags also played basketball for Latvia on an international level, he was silver medalist of EuroBasket 1939. In 1942 during German occupation of Latvia Vanags as a player with ASK won the Latvian league title.