Martino attended Staples High School in Westport, Connecticut, where he played soccer and was named Gatorade National Player of the Year in 1998 after his senior season.
He tallied two goals and five assists in 22 appearances and won the MLS Rookie of the Year Award, while running the Crew offense for much of the season.
His following season was something of a disappointment, as Martino failed to develop into the dominant offensive force that many had expected, although he maintained a spot in the Crew's starting lineup.
During the first 2006 match between the Crew and the Galaxy, before the trade, it was Martino who, in the last few seconds, scored the game's only goal, delivering a defeat to his soon-to-be teammates.
Until the beginning of the 2020/21 season, Martino was a studio analyst and color commentator for NBC Sports coverage of the English Premier League.
On November 6, 2017, Martino announced he was leaving NBC Sports temporarily to stand as a candidate for president of the United States Soccer Federation in the February 2018 election.