Alston grew up in the Jamaica neighborhood of Queens, New York City, and was a standout streetball basketball player, known for his untraditional ballhandling moves that made him adept at outmaneuvering defenders.

He did not disappoint, averaging 12 points and 4 assists on a young Miami team, led by rookie guard Dwyane Wade, that made it to the Eastern Conference Semi-Finals of the 2004 NBA Playoffs.

During that season, in a March 26 game against the Dallas Mavericks, he hit a game-winning shot in overtime with 0.5 seconds left over the outstretched arms of Shawn Bradley to catapult Miami to a 119–118 victory.

Jeff Van Gundy's reputation for toughness and his ability to get the most out of players previously considered "trouble-makers" or "temperamental" (e.g., Latrell Sprewell) led to optimism on the part of the Rockets' staff.

[11] On November 12, 2008, Alston was suspended for two games without pay for his role in a fight after a non-call foul with Matt Barnes and Steve Nash.

[12] Alston was traded to the Orlando Magic in a three-way deal on February 19, 2009,[13] and replaced the injured Jameer Nelson in the team's starting lineup.

Orlando then defeated the Boston Celtics and Cleveland Cavaliers to advance to the NBA Finals, where they lost to the Los Angeles Lakers in five games, after Alston was replaced in the starting lineup by returning star Jameer Nelson.

[citation needed] On June 25, 2009, he was traded to the New Jersey Nets along with Tony Battie and Courtney Lee in exchange for Vince Carter and Ryan Anderson.

[23] On Sunday morning, August 5, 2007, Alston was arrested in downtown Houston on misdemeanor charges of assault and public intoxication.

[25] He was arrested yet again early Tuesday morning, August 28, 2007, in New York for allegedly slashing a man on the neck during a nightclub altercation.