Petersen was called up to the majors for the first time on May 6, 2010.[4] He hit a single in his first career at bat and eventually scored a run.[5]
On July 20, 2011, Peterson pitched a hitless inning of relief, walking one batter, in a game against the San Diego Padres. On September 27, when Javier Vázquez made his last Major League start, Petersen gave him a win when he hit a ninth inning walk-off home run off Nationals reliever Doug Slaten off the Bud Light advertisement in right field.[6][7]
On April 29, 2012, Petersen was recalled from Triple-A New Orleans to replace struggling outfielder Chris Coghlan, who was optioned to New Orleans. Petersen was hitting .320 with 8 runs batted in and 3 SB in 21 games at New Orleans. He finished the season batting .195 in 241 at-bats with no homers, 9 doubles, 3 triples, 17 runs batted in, 25 walks, and 8 stolen bases.
After the signing of reliever Jon Rauch to a one-year deal, the Marlins designated Petersen for assignment. He was resigned afterwards and sent to New Orleans. In 2013, he hit .275, with 33 doubles, 5 triples, 8 home runs, and 49 runs batted in while stealing 12 bases with the Zephyrs.[8]
Texas Rangers
Petersen signed a minor league deal with the Texas Rangers on December 5, 2013. He currently plays for the Texas Rangers' Triple-A affiliate, the Round Rock Express. On 3 April 2014, he hit a grand slam in a 7-6 loss to the Oklahoma City RedHawks. So far, in the 2014 season, he has hit .254, with 12 homers, 57 runs batted in, and 5 stolen bases to go with a .323 on base percentage.[9]
Milwaukee Brewers
On December 16, 2014, he signed a minor league contract with the Milwaukee Brewers. He was released on August 1, 2015.