Mark David Melancon (/məˈlænsən/ mə-LAN-sən;[1] born March 28, 1985) is an American former professional baseball pitcher.

He played in Major League Baseball (MLB) for the New York Yankees, Houston Astros, Boston Red Sox, Pittsburgh Pirates, Washington Nationals, San Francisco Giants, Atlanta Braves, San Diego Padres, and Arizona Diamondbacks.

Melancon was born in Wheat Ridge, Colorado, and attended Golden High School, where he lettered all four years in baseball, basketball and three times in football.

He played a shortened season in 2006 due to a strained elbow ligament, and had a college career total of 18 saves.

[7] He made his MLB debut as a relief pitcher against the Boston Red Sox on April 26, pitching two scoreless innings.

[10] On December 14, 2011, Melancon was traded to the Boston Red Sox for infielder Jed Lowrie and starter Kyle Weiland.

On December 26, 2012, the Red Sox traded Melancon, Stolmy Pimentel, Jerry Sands and Iván DeJesús Jr. to the Pittsburgh Pirates for Brock Holt and Joel Hanrahan.

Melancon avoided arbitration with the Pirates by signing a one-year contract worth $2.95 million for the 2014 season.

[24] On July 30, 2016, the Pirates traded Melancon to the Washington Nationals for Felipe Vázquez (formerly Rivero) and Taylor Hearn.

[27] Melancon began his tenure with the Giants by blowing a save opportunity on Opening Day 2017 after Madison Bumgarner had pitched well and hit two home runs in the game against the Arizona Diamondbacks.

[29] On September 4, 2017, it was announced Melancon would undergo surgery to alleviate chronic exertional compartment syndrome in his right forearm.

On July 31, 2019, the Giants traded Melancon to the Atlanta Braves for Tristan Beck and Dan Winkler.

[10] On February 18, 2021, Melancon signed a one-year contract worth $2 million with the San Diego Padres.

Melancon received a platelet-rich plasma injection in his right shoulder after suffering a strain in spring training, and was later placed on the 60-day injured list on April 9, 2023, as the injury cost him the entire 2023 season.

[36] The Diamondbacks declined their side of the mutual option on November 5, making Melancon a free agent.