Williams did not play against California last weekend and has not practiced this week, but he said he felt stronger after receiving a platelet-rich plasma injection Tuesday.
"I'm just feeling like I'm getting a lot of my strength back so I should be able to go Saturday," he said.
The 6-foot-5, 290-pound Williams is the Trojans' second-leading tackler and he has a team-best 11 tackles for loss. He is regarded as a key player against a large and physical Stanford offensive line.
"He's going to have to play, and play well," USC interim Coach Ed Orgeron said.
Williams has played through the discomfort of an injury suffered during training camp. He aggravated the problem when he fell awkwardly in the game against Oregon State.
Williams said he would make the decision about whether to play on Saturday and beyond.
"A lot of guys in the locker room are always telling me make sure that I'm ready to go because a lot of people want me to go this week," he said. "So it's kind of adding a lot of pressure."
"I don't feel like it's too much pressure," he said. "In big physical games, I'm always up for the challenge. Like Notre Dame and stuff like that.
"I just love big-time games like that. I put pressure on myself to get ready to play because I love physical games."
Two years ago against Stanford, Andre Heidari kicked 50- and 22-yard field goals and converted six extra-points in the Trojans' 56-48 triple-overtime loss at the Coliseum.
The junior missed a field-goal and extra-point attempt last week against Cal, but he said he was looking forward to playing the Cardinal in a game that could be decided by the kicking game.
"You want to prove that you can make a game-winning field goal when it's on the line," he said. "That's what I play for."
Heidari has made 11 of 18 field-goal attempts this season.
Orgeron said Sunday that he was concerned about the kicking game. Asked Wednesday if he felt any better about it, he said, "It's always a game-type deal…. If it doesn't work we're going to have to do something else.
"We're prepared to do something else — either be more aggressive or put in somebody else. We're prepared if he doesn't perform well."
Neither Alex Wood nor Craig McMahon, who are walk-ons, have attempted a field goal. Wood kicked eight extra points in 2012.
Cornerback Josh Shaw (knee) did not practice but said he would play Saturday…. Former USC defensive lineman Shaun Cody attended practice.