Strömgren began his professional career during the 2020-21 season with Modo Hockey, of the second tier Swedish league: the HockeyAllsvenskan. He would split the season with MoDo's junior league teams, as well as spending time on loan to third tier team Örnsköldsvik HF of the HockeyEttan.[1] After being drafted by the Calgary Flames in the second round, 45th overall during the 2021 NHL draft,[2] Strömgren would make his SHL debut for Rögle BK during the 2021-22 season. Strömgren struggled to maintain a consistent roster spot with Rögle, spending most of the season with their junior club.[3] Early into the 2022-23 season, Strömgren moved from the dominant Rögle team who had won the league championship the previous season, to struggling Brynäs IF following his mutual contract termination.[4][5][6] This move allowed Strömgren to have a much more significant role in the club, suiting up for 45 games with the team.[7]
North America
On March 29, 2023, the Calgary Flames signed Strömgren to a 3-year entry-level contract, beginning with the 2023–24 season.[8][9] Following his NHL contract signing, Strömgren signed an amateur-tryout (ATO) contract with the Flames top affiliate: the Calgary Wranglers of the American Hockey League.[10][11] Joining very late in the season, he would only play in two games for the Wranglers before the seasons end.
Prior to the 2023–24 NHL season, Strömgren would participate in the Young Stars Classic tournament during the Flames preseason, scoring twice in the team's matchup against the Winnipeg Jets.[12] An early cut from the Flames training camp, Strömgren was assigned to the Wranglers for the 2023–24 AHL season on September 29, 2023.[13] Strömgren would score his first AHL goal on December 23, 2023, during a 5–1 victory over the Colorado Eagles, his 24th game of the season.[14]