Williams, a junior safety, will be out for the year.
"He was a core special teams player for us," Saban said. "He was a solid backup for us."
The news comes a day after Alabama announced that cornerback Travell Dixon would be leaving the program for "personal reasons." So that's two players gone from a secondary that already lacks experience.
"Younger guys in the secondary have to be backup players," Saban said. "They have to have some roles."
Saban couldn't make an evaluation on Williams, who had been practicing at wide receiver, just yet.
"We're telling him what to do every play," he said. "It's not fair to make any evaluation because he doesn't even know how to do this stuff. We're telling him what to do, but haven't taught him how to do it. At receiver, he was big, very physical and hopefully he'll be able to add range. The big thing is being a good tackler, can he play man-to-man, can he get comfortable in the system? It may take awhile."
This is the second fatality for the Tide this week, having lost freshman wide receiver Chris Black to a season-ending shoulder injury.
For more Alabama coverage, follow Laken Litman on Twitter!