Before moving to the University of San Francisco in 2004 McDonald played for the Sereno Golden Eagles youth club with Michael Gavin, Rob Valentino and current teammate Robbie Findley.

The then-rookie shared a locker room with David Beckham and Landon Donovan while taking instruction from Bruce Arena.

After a season in Carson, McDonald moved to San Jose, where the Earthquakes finally gave him the chance to play on a regular basis.

McDonald made the most of the opportunity, starting 28 matches in 2010 as the Northern California side advanced to the Eastern Conference Finals.

In June 2017, McDonald signed for Penang FA, a club in the top division of Malaysian football, the Malaysia Super League.

In July 2014 McDonald was initially called up for the Guam national team EAFF Cup training camp but due to schedule conflicts he was unable to attend.