Born in Stockholm, Wahlstedt played youth football for AIK and Norrtulls SK, before moving to FC Djursholm.[3][4] In April 2018, he signed with recently promoted Allsvenskan club Dalkurd FF.[5] He made his professional debut for the club on 21 August 2018, starting in a 2–1 Svenska Cupen win against Karlbergs BK.[6] During his sole season at the club, he failed to make a single league appearance, only playing the one match in Svenska Cupen.[2]
In January 2019, Wahlstedt moved to Norwegian third tier club Arendal.[7] Through the first three games of the season, Wahlstedt was a backup, but he soon earned the starting job after making his debut on 1 May 2019 in the Norwegian Football Cup match against Vindbjart, which his team won 3–0.[8][2] His league debut followed three days later in a 5–3 loss to Fredrikstad.[9]
Wahlstedt joined the Eliteserien side Odd from Arendal ahead of the 2021 season as a backup for Sondre Rossbach. On 12 September 2021, he made his Eliteserien debut for the club in a 1–1 draw against Bodø/Glimt.[10] From that date, he made the place his own. In the following two seasons, he was considered the best and most potential goalkeeper in Eliteserien, with many rumors of moving to bigger clubs. Representatives from clubs such as Liverpool, Villarreal and FC Schalke 04 were present during the games at Skagerak Arena.
On 3 July 2024, Wahlstedt signed for Danish Superliga club Aarhus Gymnastikforening for an undisclosed fee.[12] He made his competitive debut for De Hvii'e on 25 September in a third-round Danish Cup game against VSK Aarhus, but was forced off after 15 minutes due to an ankle injury.[13] Initial examinations revealed a broken bone, sidelining him for an extended period.[14]
International career
In September 2022, Wahlstedt received his first call-up to the Sweden national team after a convincing season in Eliteserien.[4] He made his full international for debut Sweden on 9 January 2023, playing for 90 minutes in a friendly 2–0 win against Finland.[15]
Personal life
Wahlstedt's paternal grandfather is from Sicily, Italy.[3]