The St. Louis Cardinals selected Ottavino out of Northeastern University in the first round, with the 30th overall selection, of the 2006 MLB draft. That year, he pitched for the Swing of the Quad Cities of the Class AMidwest League. He pitched for the Springfield Cardinals of the Class AATexas League in 2008. In 2009, Ottavino pitched for the Memphis Redbirds of the Class AAAPacific Coast League. He had an 0–9 win-loss record in the first half of the season, but had a 7–3 record in the second half. After the 2009 season, the Cardinals added Ottavino to their 40-man roster. He began the 2010 season with Memphis. On May 29, 2010, Ottavino made his major league debut for the Cardinals as a starter. He appeared in five games for the Cardinals in 2010, three of them starts. After the 2010 season, the Cardinals outrighted Ottavino off of their 40-man roster. He pitched for Memphis in 2011, and the Cardinals readded him to their 40-man roster after the season.
Colorado Rockies
On April 3, 2012, the Colorado Rockies claimed Ottavino off of waivers. The Rockies assigned him to the Colorado Springs Sky Sox of the PCL. They promoted him to the majors later that season, and developed him into a relief pitcher. In 2013, Ottavino switched his uniform number to 0. Despite posting a 5–1 win-loss record, his earned run average was close to 5 in 79 innings. In 2013, Ottavino appeared in 51 games, pitching in 78.1 innings and lowering his ERA from the previous season by 2 runs, registering an ERA of 2.64 for the Rockies. In 2014, Ottavino went 1–4 with a 3.60 ERA in a career high 75 games. After closer LaTroy Hawkins struggled to open the 2015 season, Ottavino was named the new closer. On May 4, 2015, it was revealed that Ottavino had a partially torn ulnar collateral ligament in his right elbow, which required Tommy John surgery, ending his 2015 season. After the 2015 season, the Rockies and Ottavino agreed on a three year contract worth $10.4 million. Ottavino began the 2016 season on the disabled list. After returning, he completed 37 scoreless appearances, in 31 innings pitched, which set a Rockies' franchise record. In 2018, he was 6–4 with a 2.34 ERA, and shared the major league lead in holds, with 34.
On January 24, 2019, the New York Yankees signed Ottavino to a three year contract worth $27 million. Ottavino is the first Yankee in team history to wear number 0, the last single digit number available by the Yankees.
Personal life
Adam Ottavino resides in his childhood neighborhood of Park Slope, Brooklyn, New York with his wife, Brette, and their two daughters.