Donald was drafted by the Phillies in the third round (97th overall pick) of the 2006 MLB Draft. He was originally drafted by the Anaheim Angels in the 20th round of the 2003 MLB Draft, straight out of high school, but chose not to sign.
Donald was selected and participated in several All-Star games during the course of the 2008 season including the Eastern League All-Star game, and the premier event for minor leaguers, the MLB All-Star Futures Game at Yankee Stadium.
In 2009, Donald played 9 games with the Phillies as part of the Gulf Coast League, going 6 for 26 (.231) before being assigned to the Lehigh Valley Iron Pigs of the International League. While with the Pigs, Jason had a .236 batting average with one home run over the course of 51 games.
Donald and Reading teammate Lou Marson were selected to the United States national baseball team. Donald helped lead the United States to a bronze medal at the 2008 Olympics. Donald homered in the bronze medal game and led the team at the games in batting average, on-base percentage and slugging percentage. Donald batted .381 for the games.