- Bats Right, Throws Right
Jakob Claesson is the son of Robert Claesson and Yvonne Claesson and the brother of Joakim Claesson and Thomas Claesson. He debuted in the Elitserien in 2006 with Stockholm, going 3-3 with a 4.29 ERA as a 17-year-old. In 2007, he fell slightly, to 3-4, 4.80.
He pitched for Sweden in the 2007 European Championship, following his father and brother Joakim onto the national team. The club's youngest player, he struggled. In his lone game, he relieved Håkan Börjes against the Dutch national team with a 11-0 deficit and two outs in the third. Claesson began by walking Harvey Monte on a full count. He then walked Dirk van 't Klooster and Tjerk Smeets, both on five pitches. Johnny Balentina delivered a pinch-hit RBI single. Claesson walked Roger Bernadina on a full pitch, forcing in a run. Per Sjörs relieved Claesson, who had retired none and given up 4 walks, a hit and two runs.
In 2008, Claesson faded to 2-3, 5.70 for Stockholm. Despite similar numbers to start 2009, he was put on Sweden's preliminary 40-man roster for the 2009 Baseball World Cup.