7. NBA legendary center Shaquille O'Neal announced his retirement on June 1 on Twitter to end his 19-year professional career, in which he won three consecutive titles with the Los Angeles Lakers and then a fourth with the Miami Heat in 2004.

On July 20, another NBA great Yao Ming announced his retirement in a press conference in Shanghai. The Shanghai native played for eight seasons in the NBA after being the top overall pick in the 2002 draft and has been named to the NBA All-star team eight times, but he was troubled with a series of injuries.