[4] Krusnell joined the club at the same time as fellow countryman Joel Asoro, a forward from Brommapojkarna.
Krusnell signed a three-year contract, his first professional deal, with Hammarby and left Sunderland without making any senior appearances.
[9] Krusnell made his competitive debut on 21 August, coming on as a late sub, in a 3–0 away win against Örebro SK.
First at affiliated club IK Frej in Superettan and then Team TG in Division 1, Sweden's third tier.
[11] In 2020, Krusnell was also sent on loan to IK Frej, and left Hammarby at the end of the year when his contract expired.