In the late 1960s, Christensen played alongside Jan Garbarek on several recordings by the composer George Russell. He also was a central participant in the jazz band Masqualero, with Arild Andersen, and they reappeared in 2003 for his 60th anniversary.
In the late 1960s, Christensen collaborated with Jan Garbarek on recordings by George Russell. He was a central figure in the jazz band Masqualero, which included Arild Andersen, and they reunited for a performance to celebrate his 60th birthday.