On June 23, 2011, Thompson was drafted fourth overall in the 2011 NBA draft by the Cleveland Cavaliers. At the time, he was the highest drafted Canadian-born player in NBA history, that was until Anthony Bennett and Andrew Wiggins were selected with the first overall pick in 2013 and 2014, respectively. Thompson continued to make history, drafted alongside Joseph, who was picked 29th by the San Antonio Spurs, only the second occasion in NBA history to that date that two Canadians were selected in the first round of the same draft, the first being in 1983 when Leo Rautins and Stewart Granger were selected 17th and 25th respectively. The 2011 draft was also the first time three Texas Longhorn basketball players went in the first round of a draft, when Thompson's former collegiate teammate Jordan Hamilton went 26th overall to the Dallas Mavericks.