[5] At the 2001 European Amateur Team Championship at Ljunghusen Golf Club in Sweden, team Finland finished a historical high forth (behind England, Ireland and Sweden) in the qualifying stroke-play competition and lost to champions to be Scotland in the quarter-finals.

In June 2002, still an amateur, Karjalainen won the Messilä Trophy in Finland on the Nordic Golf League.

He followed that up in 2006 by winning again on the Challenge Tour, the Telenet Trophy at the Limburg Golf and Country Club in Belgium in a last round interrupted by thunderstorms.

His best finish on the European Tour was tied 20th at the 2006 BA-CA Golf Open in Vienna, Austria.

[9] Having lost his playing privileges in Europe at the end of the 2008 season, Karjalainen joined the Asian Tour in 2009 after coming through qualifying school.