Lester Holt has been the jack of all trades at NBC News.

Seemingly he has appeared on every NBC News program at one time or another. But, tonight he takes on his biggest role yet.

Tonight, Holt steps into Brian Williams seat on NBC Nightly News with the goal of trying to keep the "NBC Nightly News" competitive and credible until the Brian Williams firestorm and jokes subside.

The NY Daily News says that Holt's primary task is to reassure viewers that NBC News, the organization, has separated itself from the inconceivably foolish "conflation" blunder that led Williams to say Friday he's taking himself off the air for a while.

Sources tell FTVLive that Holt has big fans inside 30 Rock. "Great guy and exemplary work horse," says one NBC insider to FTVLive.

There is no word on how long Holt will be filling in for BriLie. NBC says that Williams is taking, "several days off."

Sources tell FTVLive that if NBC decides to cut ties with Brian Williams, then NBC is looking to 3 people as a possible replacement. They are Holt, Jose Diaz Balart, and Peter Alexander.

If it comes to the point where Lying Brian is kicked to the curb, look for the NBC newsroom to lobby hard for Lester Holt to get the gig.