Carter has spent his 8 years as a pitcher in the minor league systems of the Chicago White Sox and the Boston Red Sox. The right-hander was drafted by Chicago in the 26th round of the 2005 MLB draft. From 2006-2012, he played in every level of the White Sox organization. He began his career as a starter until 2010 when he became a reliever. In 2013, he signed with the Red Sox organization and spent the season with Boston's AAA team in Pawtucket.
Carter has a minor league career ERA of 4.58 and is coming off his best year in which he sported a 3.47 ERA in 52 games pitched. As Brock stated in his tweet, Carter had a 11.4 K/9, which he compiled last year. That mark was highest throughout his career.
As I said earlier, the Red Sox picked up former Padres reliever Tommy Layne.
Layne was designated for assignment when Cory Luebke and Joe Wieland were reinstated to the Padres 40-man roster last month. The left-hander spent 40 games with the Padres over his 2 seasons on the majors, though the majority of 2013 was spent in the minors with Tucson.
The signing of Carter brings another potential arm to the Padres bullpen in 2014. We will see what the future holds for Carter. For now, welcome to the Padres organization.