Mascherano, 40, is a former teammate of Miami star Lionel Messi. The two were teammates at FC Barcelona from 2010-18.
Miami had won the regular season campaign with a record points total but after losing twice in the best-of-three series, the MLS Cup favourites and their eight-times Ballon d'Or winner are out.
Portuguese winger Xande Silva blasted home a sensational winner for Atlanta in the fourth minute of stoppage time in front of 68,455 home fans at the Mercedes-Benz Stadium to level the best-of-three postseason series 1-1 and set up a winner-take-all game three in Miami next Saturday.
Miami started with all their big-name stars, including Lionel Messi, on the bench but the Argentine was introduced in the 61st minute to the delight of many in the Toronto crowd.
Messi had been subdued until the 45th minute when he put Inter ahead -- chesting down a long ball into the box and getting a lucky bounce off Crew defender Malte Amundsen before poking home.
Messi tied Saturday's match in the 67th minute when he lasered a shot from beyond the box that evaded diving Charlotte goalkeeper Kristijan Kahlina to make it 1-1.
Inter Miami's charge towards Major League Soccer's single-season points record suffered a setback on Saturday after a last-gasp injury-time equalizer from James Sands snatched a 1-1 draw for New York City FC against the Eastern Conference leaders.
The Argentinian superstar Messi came close to a game-clinching goal in the 83rd, but his angled effort was blocked by Atlanta goalkeeper Brad Guzan and Suarez's attempt to tap in the rebound was also denied.
The eight-times Ballon d'Or winner hadn't played since injuring his right ankle during the Copa America final on July 14, when he helped Argentina to victory over Colombia.
Messi's first game with the team could be on July 21 when Inter Miami host Cruz Azul in their Leagues Cup opener in Fort Lauderdale
Barcelona said in a statement that Messi's father and agent had informed the club on Monday of his decision to move to America instead of returning to Spain
Lionel Messi will sign for Major League Soccer side Inter Miami, the player said Wednesday in interviews with Spanish media, choosing the United States as his next destination over a Barcelona reunion or blockbuster deal to play in Saudi Arabia.
Lionel Messi will snub a lucrative contract in Saudi Arabia and move to Major League Soccer side Inter Miami as a free agent after parting ways with French champion Paris St Germain, the BBC reported on Wednesday.
Lionel Messi is set to leave PSG in the summer and has been linked with former club Barcelona, along with MLS side Inter Miami.
Teams around the world are starting to express interest in Messi as his deal with Paris Saint-Germain expires in June.
Barcelona's new signing Raphinha shone with a goal and two assists in his pre-season debut as the Spanish giants thrashed Inter Miami 6-0 in their U.S. tour on Tuesday.
Robert Lewandowski will bring the 'winning mentality' Barcelona need according to new team-mate Andreas Christensen.
