Mathias Ullereng Kjølø

Mathias Ullereng Kjølø left Vålerenga for the PSV Eindhoven academy while still in his teens. He spent three seasons with Jong PSV in the Eerste Divisie, making 75 appearances and scoring five goals for the reserves, and in November 2020 he was given a single senior outing for PSV Eindhoven in the Eredivisie.

A permanent move to FC Twente followed in June 2022, on a three-year deal with an option for a fourth. Kjølø became a regular starter in Enschede, going on to make 129 appearances across all competitions, including 100 in the Eredivisie, where he scored once, plus six KNVB Cup outings and twenty in European competition. Neither PSV nor Twente delivered a major trophy during his time there.

Kjølø's rise was also tracked through the Norway youth setup, where he moved through the age groups from under-16 to under-21 level. A senior cap for Norway has so far eluded him.

On 31 August 2026, Kjølø returned to Rosenborg BK, the club where he began as a youngster, signing a contract that runs to 2030. As of early September he was yet to make his league debut for his new side.