Alexander attended Portage Central High School, where he was named NSCAA/adidas Boys High School National Player of the Year and Gatorade National Boys Soccer Player of the Year in 2005, before playing college soccer for the Indiana University Hoosiers from 2006 to 2009.

Alexander was traded to Portland Timbers on August 19, 2011, after making 22 league appearances during the 2011 campaign for FC Dallas in exchange for Jeremy Hall.

[6] After a season and a half with Montreal, Alexander was traded to the Houston Dynamo in exchange for general and targeted allocation money.

In 2017 he helped the Dynamo make the playoffs for the first time in 3 seasons, however Alexander suffered a MCL sprain on May 6 that caused him to miss 4 months.

On January 3, 2014, he was again called up, this time as part of a 26-man roster that trained in Carson, California and São Paulo, Brazil as coach Jürgen Klinsmann prepared the side for the 2014 FIFA World Cup.