Oscar Linnér

AIK

Linnér made his debut for AIK in a UEFA Europa League qualifier match against VPS.

Arminia Bielefeld

On 7 January 2020, Linnér joined Arminia Bielefeld on a three-and-a-half-year deal.

Loan to Brescia

On 11 August 2021, Linnér joined Serie B club Brescia on a season-long loan deal, with an option to buy.

Loan to Sundsvall

On 6 February 2022, Linnér was loaned to Sundsvall. However, he left the club after only two months. On 24 August 2022, Linnér's contract with Arminia was dissolved.

AaB

With first goalkeeper Josip Posavec injured, Danish Superliga club AaB confirmed on 16 October that they had signed Linnér to a short contract for the remainder of 2022.

Vendsyssel

After a short spell at IF Brommapojkarna in Sweden, Linnér returned to Denmark, signing a short-term deal with Danish 1st Division club Vendsyssel FF until the end of the season. On May 29, 2024, Vendsyssel confirmed that Linnér would leave the club at the end of June 2024.

Petrolul Ploiești

On 5 November 2024, Linnér joined Romanian Liga I club Petrolul Ploiești on a deal until June 2026.

KTP

On 2 July 2025, Linnér signed with KTP in Finnish Veikkausliiga for the remainder of the season.

Falkenberg

In June Linnér joined Superettan side Falkenbergs FF on short-team deal due to injuries to the keepers at the club. On 1 July 2026, he left the club again.

Linnér made his debut for the Sweden national team on 11 January 2019 in a friendly against Iceland, as a starter.

As of match played 2 July 2026

Oscar Linnér has a two-years-younger brother, Albin Linnér, who is also professional footballer.