Career
Wännström made his professional debut with his original club, Brynäs IF of the Swedish Hockey League. He was drafted in the second round, 44th overall by the Saint Louis Blues of the National Hockey League in the 2010 National Hockey League Entry Draft. Wännström"s first Elitserien goal was a game winning penalty shot on October 20, 2011 against Johan Gustafsson of Luleå High Frequency. After completing the final year of his entry-level contract with the Saint Louis Blues, failing to establish himself in American Hockey League with Blues affiliate, the Chicago Wolves, Wännström returned to his native Sweden in signing a two-year contract with Rögle BK of the SHL on May 19, 2015.