Brian Williams underwent knee replacement surgery on Tuesday.
The "NBC Nightly News" anchor told viewers last week that after 35 years of pain in his right knee, he had finally made the decision to get a knee replacement.
We are happy to report that Brian's knee replacement surgery went well and he is resting comfortably tonight
— NBC Nightly News (@nbcnightlynews) August 6, 2013
Williams is expected to be out on leave for a few weeks. During his absence, "Nightly News" weekend anchor Lester Holt will take over the weeknight program.