Karlsson was a member of the Continental Europe team in the Seve Trophy in 2000, 2002 and 2007. In 1999 he was eleventh on the Ryder Cup qualifying table just missing out on the last automatic place, and was not selected as a captain's pick. He made his Ryder Cup debut in 2006, at the age of 37, along with fellow Swede Henrik Stenson. He played again in 2008, forming a partnership with Pádraig Harrington in the foursomes and beating Justin Leonard 5 &amp; 3 in the singles on Sunday.