Markus Carl Olof Karlsson (born 20 January 2004) is a Swedish professional footballer who plays as a right back or centre-back for Hammarby IF in Allsvenskan.
Born and raised in Stockholm, Karlsson started to play youth football with local club Hammarby IF in 2009, at age five.
[2] In 2022, he mostly played for feeder team Hammarby TFF in Ettan, Sweden's third tier, making 19 league appearances.
[5] On 25 February 2023, Karlsson made his competitive debut for Hammarby, coming on as a substitute in a 3–0 away win against Norrby IF in Svenska Cupen.
[6][7] On 25 May 2023, he made his league debut in Allsvenskan, starting as a right back away against Degerfors IF and scoring 0–1 with a left-footed shot in the top corner in a game that would end 2–2.