Update from Ross Siler, (10:23 a.m. MST),
Learning more about the situation...Deron Williams left because of family medical reasons that he wants to keep private for now.
Williams might make a public announcement later in the day.
From @lockedonsports,
Utah Jazz Deron Williams has left the Jazz for personal reasons. He is excused. Ronnie Price is also out.
And @tribjazz,
Deron Williams has left the Jazz for personal reasons and won't play tonight in Philadelphia.
The situation is still developing. Eric Maynor will start. No word on whether Williams can make it to Cleveland for Saturday.
Hope all is well.