Alston was drafted in the first round (10th overall) of the 2009 MLS SuperDraft by New England Revolution after signing a Generation Adidas contract with Major League Soccer.
He made his professional debut on March 21, 2009, in New England's first game of the 2009 MLS season against the San Jose Earthquakes.
 Alston was selected to his first Major League Soccer All-Star Game during the 2010 season and was in the starting lineup for the match in Houston against Manchester United.

Alston scored his first professional goal in the final of SuperLiga 2010, but the Revolution lost 2–1 to Monarcas Morelia of Mexico.
Alston scored his first league goal April 12, 2014 at home against the Houston Dynamo.

Alston scored his first Major League Soccer goal on April 12, 2014 in 2–0 victory against Houston Dynamo.
Alston was drafted in the first round (10th overall) of the 2009 MLS SuperDraft by New England Revolution after signing a Generation Adidas contract with Major League Soccer. He made his professional debut on March 21, 2009, in New England's first game of the 2009 MLS season against the San Jose Earthquakes.  Alston was selected to his first Major League Soccer All-Star Game during the 2010 season and was in the starting lineup for the match in Houston against Manchester United.
Alston scored his first professional goal in the final of SuperLiga 2010, but the Revolution lost 2–1 to Monarcas Morelia of Mexico. Alston scored his first league goal April 12, 2014 at home against the Houston Dynamo.
Alston scored his first Major League Soccer goal on April 12, 2014 in 2–0 victory against Houston Dynamo.
Kevin Alston