Vieira is coming on in place of Matt Lauer, who has filled in for the last three days as Costas continues to deal with the effects of an infection that began in his left eye and spread to his right eye earlier this week. Costas called Lauer in from the "bullpen" on Tuesday, ending a streak of 157 consecutive appearances as NBC's Olympics anchor in prime time. It was the first time since 1988 that Costas did not host the coverage.
"It's an honor to fill in for him,'' Vieira said on TODAY Friday. "You think about the Olympics, and you think the athletes and then Bob Costas."
"Bob’s eye issue has improved but he’s not quite ready to do the show," NBC Olympics Executive Producer Jim Bell told TODAY.com from Sochi on Thursday. "If your eyes are sensitive to bright lights, a TV studio is not the place to be."
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