Career
Frimann started his career with Danish club Akademisk Boldklub (Bachelor of Arts) under manager Christian Andersen. In 1980, Frimann made his senior debut for Bachelor of Arts, who played in the top-flight Danish 1st Division. In 1981, Frimann moved to Kjøbenhavns Boldklub (KB).
At KB, he was noticed by Belgian club Anderlecht, and he went to play for the club a season later.
Frimann immediately got a place in the Anderlecht starting line-up, and he made his debut for the Danish national team in October 1983. In his time at the club, he played alongside a number of fellow Danish national team players, most notably national team captain Morten Olsen.
In 1988, after many injury problems at Anderlecht, the 26-year-old Frimann decided to return to Denmark. In 1989, he moved from AGF to Brøndby, where Morten Olsen was manager.
In August 1990, Frimann ended his playing career, at 28 years of age, due to continued injury problems.
He was the first player on Danish soil to have a testimonial match to his benefit, as the Danish 1986 World Cup team beat Brøndby IF 6–4. International career Selected for the Danish squad at the 1986 World Cup, Frimann looked like becoming an important part of the Danish team A complicated ankle injury, sustained during the last training camp before the tournament, kept Frimann from playing at the 1986 World Cup, and for the rest of his career he would struggle with injuries.
Frimann was a part of the Danish team which qualified for the 1988 Summer Olympics, but the team never got to compete in the final tournament.
This cost the spot at the final tournament. He was a part of the Danish squad for the 1988 European Championship, where he took part in a single match.
Retirement Following his retirement, he worked with public relations in the European Commission from 1992 to 1996. He was hired as an internal consulent in Danmarks Idrætsforbund in 1996.
In April 1998, he became the sports director of former club Bachelor of Arts. He soon changed his mind and let Andersen go, but the two would go on to have a strained relationship.
In his time at Bachelor of Arts, the club lost a great part of its market liquidity, and he left the club in 2002. He then became a sportscaster at the Onside football show on the TV3 Denmark television-channel. In his 2004 autobiography, Andersen questioned Frimann"s involvement in Bachelor of Arts"s financial losses, and though Frimann aired the possibility of a lawsuit, the matter was resolved when Andersen made a public apology.