Aaron Hill's journey through Major League Baseball began when he was drafted by the Toronto Blue Jays in the first round of the 2003 MLB Draft. A talented infielder, Hill quickly rose through the minor league ranks, making his MLB debut with the Blue Jays in 2005. Known for his solid defensive skills and ability to play both second base and shortstop, Hill became a regular fixture in the Blue Jays' lineup.

In 2007, Hill had a breakout season, hitting .291 with 17 home runs and 78 RBIs. His performance earned him the American League Silver Slugger Award for second basemen, highlighting his offensive prowess. However, his career faced a setback in 2008 when he suffered a concussion that limited his playing time. Despite this challenge, Hill returned to form in 2009, achieving career highs with 36 home runs and 108 RBIs. This remarkable comeback season earned him an All-Star selection and another Silver Slugger Award.

Hill's tenure with the Blue Jays continued until 2011 when he was traded to the Arizona Diamondbacks. In Arizona, Hill continued to demonstrate his abilities on the field. The 2012 season was particularly noteworthy as he hit for the cycle twice in June, becoming the first player in a decade to achieve this feat twice in one season. His performance that year included a .302 batting average, 26 home runs, and 85 RBIs, earning him a Silver Slugger Award in the National League.

Over the next few years, Hill remained a steady presence in the Diamondbacks' lineup, though his offensive numbers began to decline. In 2016, he was traded to the Milwaukee Brewers, where he played for part of the season before being traded again to the Boston Red Sox. Hill's time with the Red Sox was brief, and he became a free agent at the end of the season.

In 2017, Hill signed a minor league contract with the San Francisco Giants but was released before the start of the regular season. This marked the end of his professional playing career. Throughout his time in MLB, Hill was known for his defensive reliability and occasional power at the plate, making him a valuable player for the teams he played with.