Fox was drafted as a catcher by the Chicago Cubs in the third round of the 2003 Major League Baseball draft. From 2003 to, he spent parts of each season in Single-A ball for the Lansing Lugnuts and the Daytona Cubs, before moving on to Double-A in mid-2006. As a member of the Lugnuts, Fox was given the opportunity to catch for then-Cubs pitcher Mark Prior, who was on a rehab assignment. He was ecstatic to catch for Prior, and even invited his family members to attend the game. However, upon arriving at the club house, he found out that Paul Bako was actually slated to catch the game. Fox approached his manager, Julio Garcia, who claimed that Fox was not experienced enough to catch a Major League pitcher like Prior. Garcia then revealed that the team was playing a practical joke on Fox, and that he would actually be in the team's lineup. On July 19, 2007, Fox was called up from Double-A Tennessee to the major leagues after shortstopCésar Izturis was traded to the Pittsburgh Pirates. Fox was called up with the intent that he would play first base, outfield, and be the third catcher. He made his major league debut on July 19, 2007, against the San Francisco Giants in a pinch hitting role and grounded into a double play. He had his first career hit on August 15 against Phil Dumatrait of the Cincinnati Reds, a double. Fox hit his first career home run on June 25, 2009 against Armando Galarraga of the Detroit Tigers. On August 29, 2009, Fox hit his first career grand slam against Bobby Parnell of the New York Mets. In Triple-A with the Iowa Cubs in 2009, Fox had a breakout year. He was batting.423 and had hit 17 home runs and 50 RBIs by June 1, 2009, and was leading the PCL in both of these categories along with RBI, slugging percentage, and OPS. He was recalled to the Cubs on May 27, 2009. Fox was optioned back to Triple-A Iowa on June 10, 2009, and was recalled to the Chicago Cubs again on June 16. He achieved success as a part-time utility player, capable of filling in at corner outfield and infield positions, as well as catcher.
Oakland Athletics
On December 3, 2009, the Oakland Athletics acquired Fox along with Aaron Miles, from the Chicago Cubs for Jeff Gray, Matt Spencer and Ronny Morla.
Baltimore Orioles
On June 22, 2010, Fox was traded to the Baltimore Orioles for Ross Wolf and cash considerations. In Spring Training in 2011, he led the major leagues in home runs, with 10, and extra base hits, with 17. He was designated for assignment on June 1, and elected free agency on November 2.
Pittsburgh Pirates
The Pittsburgh Pirates signed Fox to a minor league contract in November 2011, and released him in June 2012.
On January 8, 2016, the Philadelphia Phillies signed Fox to a minor league contract. He became a free agent on November 7, 2016. On July 29, 2017, Fox signed a minor league deal with the Philadelphia Phillies. He elected free agency on November 6, 2017.
Coaching career
Fox was named as the hitting coach of the Augusta GreenJackets for the 2019 season.
Post-Career
After a successful career in Minor and Major League Baseball, Fox entered the business world with his own brand The Fox Code, a lifestyle and clothing line inspired by the lessons he learned from the sport.
