He played college basketball for the Louisiana Ragin' Cajuns and represented the United States at the 2015 Pan American Games in Toronto.

[1] Long originally enrolled at Mississippi State University of the Southeastern Conference, but became immediately unhappy with his choice.

[2] Long first suited up for the Ragin' Cajuns in the 2012–13 season, averaging 15.5 points and 10.2 rebounds per game to earn Sun Belt Conference Freshman of the Year and second-team All-conference honors.

He was also selected for the National Association of Basketball Coaches (NABC) college All-Star game to be held at the 2016 Final Four in Houston.

Philadelphia had to use an NBA hardship exemption in order to sign him as he made their roster stand at 16, one over the allowed limited of 15.

[13] On June 28, 2017, Long was traded to the Houston Rockets in exchange for a 2018 second-round pick and cash considerations.

[15] On October 10, 2017, Long signed a two-month contract with the Xinjiang Flying Tigers of the Chinese Basketball Association.

[29] Long represented the United States national team[30] at the 2015 Pan American Games,[31] where he won a bronze medal.