Hamilton was selected by the Cardinals in the second round of the 2006 Major League Baseball Draft, which was a supplemental pick for loss of free agent infielder Abraham Núñez. He was added to the Cardinals' 40-man roster following the 2009 season to protect him from the Rule 5 Draft.
St. Louis Cardinals
On September 18, Hamilton's contract was purchased by the Cardinals and he was promoted to the major leagues.[7] A year later after his debut, the Cardinals advanced to the postseason and eventually won the 2011 World Series over the Texas Rangers.
Hamilton was optioned to Triple-A to begin the 2012 season and was released from the Cardinals organization on August 18, 2012.
Boston Red Sox
On January 4, 2013 Hamilton signed a minor league deal with the Boston Red Sox that included an invitation to spring training. Hamilton was optioned to the Triple-A Pawtucket Red Sox to begin the 2013 season.
Atlanta Braves
In December 2013, Hamilton signed a minor league contract with the Atlanta Braves that included an invitation to spring training.[8] He was released on July 26, 2014.