Not many players win the Stanley Cup with different teams in consecutive years, but Maroon is one of them. After helping his hometown St. Louis Blues win their first championship in 2019, he signed with the Tampa Bay Lightning on Aug. 24, 2019, and was a valuable role player during their runs to the Cup in 2020 and 2021.

Maroon came home when he signed with the Blues on July 10, 2018, 11 years after the Philadelphia Flyers selected him in the sixth round (No. 161) in the 2007 NHL Draft.

He had a 40-goal, 95-point season with St. Louis of the North American Hockey League during his draft year and followed that with 35 goals and 90 points for London of the Ontario Hockey League in 2007-08.

But Maroon, a power forward, spent much of the next five seasons with the American Hockey League affiliates of the Flyers and Anaheim Ducks, who acquired him in a trade on Nov. 21, 2010, and had 32 goals and 74 points for Syracuse in 2011-12. He played 15 NHL games with Anaheim during the 2011-12 and 2012-13 seasons before becoming a regular in 2013-14, when he had 11 goals and 29 points in 62 games.

Maroon began as a fourth-line forward with the Ducks, but his work with Ryan Getzlaf and Corey Perry during the 2015 Stanley Cup Playoffs drew notice around the NHL. His ability to use his body effectively along the boards and in the tough areas helped create space for his linemates to create scoring chances. He scored 11 points (seven goals, four assists) during the 2015 playoffs but was traded to the Edmonton Oilers on Feb. 29, 2016.

The Oilers saw his size and physicality as qualities they could use, but Maroon also gave them offense right away. In 16 regular-season games with Edmonton, he had 14 points (eight goals, six assists), then had NHL career highs in 2016-17 with 27 goals and 42 points to help the Oilers qualify for the Stanley Cup Playoffs for the first time since 2006. He contributed eight points (three goals, five assists) in 13 postseason games.

Maroon scored 30 points (14 goals, 16 assists) in 57 games for the Oilers in 2017-18 before being traded to the New Jersey Devils on Feb. 26, 2018. He helped the Devils advance to the playoffs for the first time since 2012 with 13 points (three goals, 10 assists) in 17 games after the trade.

In his first season with the Blues, Maroon had 28 points (10 goals, 18 assists) in 74 games. He also scored the series-deciding goal in double overtime of Game 7 against the Dallas Stars in the 2019 Western Conference Second Round on the way to winning the Stanley Cup. He had seven points (three goals, four assists) in 26 playoff games.

However, the Blues opted not to re-sign Maroon. He became a free agent and signed with the Lightning. Maroon scored 23 points (nine goals, 14 assists) in 64 regular-season games and six points (one goal, five assists) in 25 postseason games during Tampa Bay's Cup run.

Maroon was traded to the Minnesota Wild by the Lightning on July 2, 2023, for a seventh-round pick in the 2024 NHL Draft. He was traded to the Boston Bruins by the Minnesota Wild on March 8, 2024, for Luke Toporowski and a conditional sixth-round pick in the 2026 Draft.

Maroon signed a one-year, $1.3 million contract with the Chicago Blackhawks on July 1, 2024. He announced he would retire from the NHL in March of 2025 and played his final game April 13, a 5-4 shootout loss to the Winnipeg Jets at United Center.