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Alex, 26, made just one appearance for the Fire this year but had made 48 starts since joining Chicago in April 2012. The Brazilian midfielder recorded three goals and two assists in 76 regular season appearances for the club, and scored Chicago's goal in their 2-1 loss to Houston in the Eastern Conference Wild Card game in October 2012.
Johnson, 24, has played just 614 minutes and appeared in only 21 MLS games since being taken by Houston in the first round of the 2013 MLS SuperDraft, scoring just once in league play. A Generation adidas forward who can line up in the middle or out wide, he spent much of the 2014 season on loan to the Pittsburgh Riverhounds, where he totaled one goal and one assist in 12 games.
Both players occupy domestic roster slots as Green Card holders.