Born in Brawley, California, Romo grew up a Dodgers fan. He attended four colleges, getting drafted in the 28th round of the 2005 draft by the Giants. He reached the major leagues in 2008 and appeared in 45 games for the Giants in 2009. In 2010, he became the setup man for Giants closer Brian Wilson as the Giants won the 2010 World Series. He posted a 1.50 earned run average (ERA) in 2011, then became the closer for the Giants in 2012, recording three saves during the 2012 World Series as the Giants won the title. He was an All-Star in 2013, and though he lost the closer role the next year, he won his third World Series ring as the Giants defeated the Kansas City Royals in the 2014 World Series.