Mark Trumbo's journey in Major League Baseball began when he was drafted by the Los Angeles Angels of Anaheim in the 18th round of the 2004 MLB Draft. After several years of honing his skills in the minor leagues, he made his MLB debut with the Angels in September 2010. Trumbo quickly established himself as a power hitter, known for his ability to hit home runs and drive in runs.

In 2011, Trumbo's first full season in the majors, he played primarily as a first baseman and outfielder. He finished the season with 29 home runs and 87 RBIs, earning him a second-place finish in the American League Rookie of the Year voting. His performance solidified his role as a key player in the Angels' lineup.

Trumbo continued to demonstrate his power at the plate over the next few seasons. In 2012, he hit 32 home runs and was selected to his first All-Star Game. The following year, he set a career-high with 34 home runs and 100 RBIs. Despite his offensive prowess, Trumbo's defensive versatility was often tested as he was moved between first base, the outfield, and designated hitter roles.

In December 2013, Trumbo was traded to the Arizona Diamondbacks as part of a three-team deal. His time with the Diamondbacks was marred by injuries, limiting his playing time and affecting his performance. In 2014, he played in only 88 games but still managed to hit 14 home runs.

Trumbo's stint with the Diamondbacks ended in June 2015 when he was traded to the Seattle Mariners. He finished the 2015 season with 22 home runs between the two teams. In December of that year, Trumbo was traded again, this time to the Baltimore Orioles.

The 2016 season with the Orioles marked a career highlight for Trumbo. He led the major leagues with 47 home runs, earning him the Silver Slugger Award and a second All-Star selection. His performance helped the Orioles secure a spot in the postseason, although they were eliminated in the Wild Card Game.

Trumbo re-signed with the Orioles on a three-year contract in January 2017. While he continued to be a power threat, his home run totals decreased over the next two seasons. Injuries again played a role in limiting his playing time, particularly in 2018 and 2019.

Injuries ultimately led to Trumbo's decision to step away from playing after the 2019 season.