He was drafted in the 16th round of the 2000 MLB Draft by the Tampa Bay Devil Rays. Shields played in the minor leagues and made his MLB debut for the Devil Rays in 2006 where he played until 2012. After the 2008 season he was signed to a four year deal worth $11.25 million. He was traded to the Kansas City Royals in 2012 and in 2013 they exercised a $13.5 million option for the 2014 season. Shields was named an MLB All-Star in 2011. Through the 2014 season he has 114 wins and 90 losses and 1,626 strikeouts. James is the first cousin of former Chicago White Sox outfielder Aaron Rowand.