On November, 2010, after playing in Puerto Rico and China, Williams joined the Texas Legends of the D-League. He played 49 games during the 2010–11 regular season (46 games as a starter), averaging 14.4 pts, 2.9 blocks, 9.4 rebounds and 0.8 steals per game. He was selected to the 2011 NBA D-League All-Star Game, along with his Legends teammate Joe Alexander. Williams earned a spot in the 2011 All-NBA Development League Third Team and also ranked second in voting for the Defensive Player of the Year category. Williams had more first place votes than Chris Johnson, but Johnson still won the award.