"The treatment stuff is being evaluated," Theus said. "We don't know which route they're going to take.
"I just heard there's a couple of different scenarios. One is six weeks, the other is 10 weeks. Either way it goes, we've got to make some adjustments."
The exact timing of the injury was uncertain. Bibby traveled to Las Vegas with the Kings on Thursday for their exhibition game against the Los Angeles Lakers but returned to Sacramento before the game on Friday. He underwent a magnetic resonance imaging exam Friday morning. Theus said he was not certain exactly when Bibby sustained the injury.
"He said it happened the other day in practice, but I didn't see him fall or anything," Theus said.
Bibby started every game last season and averaged 17.1 points and 4.7 assists for the Kings last season. In seven preseason games this month he averaged 13.4 points and three assists.
Second-year guard Quincy Douby started Friday's game against the Lakers and is expected to take over the point guard duties while Bibby's status is determined.
"It's tough for me, because he was playing so hard," Theus said. "His attitude was just tremendous. Basically the players looked to him as the leader of the team in a lot of ways. To have that happen, it's a tough situation. But it's part of the game, you have to shake it off and figure out a way to get it done. Talent level is important in the league, it still doesn't stop the theory of wanting to play harder than the other team."
The Kings will also be without Ron Artest for the first seven games of the season while he serves a seven-game suspension for a no contest plea to infliction of injury on his wife. Artest is appealing the suspension. Also, the Kings lost rookie center Spencer Hawes to a knee
injury during training camp.
Bibby experienced a similar injury last season when he injured his right thumb in a preseason game against the Hornets. He was diagnosed with a mallet thumb -- an injury in which a finger tendon becomes detached from a bone, preventing the finger from fully extending.
Initially, the Kings didn't expect him to play for at least three weeks, but he played through the injury. It may have affected Bibby as he shot a career-low 40.4 percent from the field.
The 10th-year pro has been with
Sacramento for the past six seasons, missing just two games over
the previous four years.
Information from The Associated Press was used in this report.
J.A. Adande joined ESPN.com as an NBA columnist in August 2007 after 10 years with the Los Angeles Times. Click here to e-mail J.A.