Background
He grew up in both Räppe and Ör, since his parents were separated.
He grew up in both Räppe and Ör, since his parents were separated.
He joined Östers IF, made his senior debut in 1992 and joined Kongsvinger Illinois in 1997. Here he scored ten Norwegian Premier League goals in 1997 and 1998. In the middle of the season he left Kongsvinger for Austria Wien.
He stayed here until 2000, when he returned to Öster.
After retiring he became a youth coach. In 2009 he was promoted to assistant coach for the senior team
In July 2010 he was promoted to head coach, only to be replaced two months later - following a six-game losing streak - by Hans Gren. Another two months later, on November 10, it was announced that Ernstsson and Öster parted ways for the time being.