Zetterberg signed his first professional contract with Allsvenskan side Falkenbergs FF in June 2015 after coming through the club's youth system.[2] On 21 February 2016, he made his senior debut in the Svenska Cupen in a 2–0 win over Tenhults IF.[3] He made his league debut on 30 October 2016 in a 4–1 loss to Helsingborg.[3] Zetterberg went on to make two league appearances in total that season.[3]
Zetterberg failed to make a first-team appearance in the 2017 season in the Superettan.[3] The following year, he made six league appearances for Falkenbergs FF before departing mid-season.[3]
Varbergs BoIS
On 10 July 2018, Zetterberg signed for Superettan side Varbergs BoIS.[4] He made five league appearances for Varberg that season and one appearance each in the league and Svenska Cupen in 2019.[3] On 30 August 2019, Zetterberg was sent on loan to Ettan side Tvååkers IF, where he made eight appearances before the end of the season.[3]