Pines becomes the fifth Terp to go pro after 2018's national championship.
After a national title, the Terps' four captains are turning pro.
Pines joins goalkeeper Dayne St. Clair in forgoing his final year.
St. Clair will be available in the MLS SuperDraft on Jan. 11.
The Terps had a bumpy start, then won nine of their last 11 games en route to the national title.
Forwards Eric Matzelevich and DJ Reeves and Matt Di Rosa impressed off the bench
Sejdic was the NCAA tournament Most Outstanding Player.
Amar Sejdic scored a 57th-minute penalty kick to secure the Terps' national championship
The Terps held Hoosiers star Andrew Gutman to one shot.
After losing to the Hoosiers twice this season, the Terps finally got their revenge.