Roberts attended Baylor University for two seasons, where he made the Big 12 All-Freshman Team, but transferred to Mississippi State University in 2003 following the basketball scandal that rocked Baylor's program that year. He was a first-team All-American and the SEC Player of the Year in 2004, leading Mississippi State to its first top-two seeding in the NCAA tournament. In the 2003–04 season he averaged 16.9 points and 10.1 rebounds. He was first-team All-SEC and a first-team All-American, finishing third to Jameer Nelson and Emeka Okafor for national player of the year honors. In the 2004–05 season he averaged 16.9 points and 11 rebounds. He recorded the first triple-double in Mississippi State history against Nicholls State University with 18 points, 11 rebounds, and 12 assists, while wearing an irritating translucent plastic face mask to protect his broken nose.
After two seasons with the Grizzlies, in July 2007, Roberts moved to Europe and signed with Greek powerhouse Olympiacos on a two-year deal. However, in October 2007, he was released from his contract before the season started. Without a club and not playing competitive basketball for several months, Roberts was signed by Serbian team KK Crvena zvezda on September 17, 2008, to a one-year contract. On September 25, 2009, Roberts was signed to the Indiana Pacerstraining camp roster, but got released less than a month later on October 19, 2009. Two days later, October 21, 2009, Roberts signed a one-year contract with KK Partizan. With Partizan he won the 2009–10 Serbian National Championship, the 2010 Serbian National Cup, the 2010 Adriatic League and took 4th place at the Euroleague's Final Four in Paris. In July 2010, Roberts signed with the Turkish team Efes Pilsen. On July 12, 2011, Roberts signed with BC Lietuvos rytas. In July 2012, he signed with Bayern Munich. In October 2013, he signed with Darüşşafaka of the TBL2. On October 2, 2014, Roberts signed with BCM Gravelines of the French LNB Pro A averaging 4.7 points and 4.9 rebounds. On February 4, 2015, Roberts left the team citing personal reasons.
Career statistics
NBA
Regular season
Euroleague
Personal
Roberts is the son of Lawrence E. "Butch" Jr., and Cynthia Roberts, nephew of former sportscaster Robin Roberts of Good Morning America fame and grandson of the late Col. Lawrence E. Roberts, Sr and Lucimarian Roberts.