SochiOlympicsNBCUPDATE, 5 PM PT: “Welcome to NBC’s primetime coverage on this Monday — I’m Bob Costas, sitting in tonight for Matt Lauer and Meredith Vieira,” Costas joked at the top of tonight’s NBC primetime Sochi Olympics coverage. He was returning to Games coverage for the first time after nearly a week off while doctors treated an infection in both of his eyes. A few moments later, more seriously, he offered “sincere thanks to Matt Lauer and Meredith Vieira – two friends and true pros who stepped in for me on short notice. My thanks as well to all of you who expressed your concern, and my apologies to everyone for the unavoidable but uncomfortable circumstance of a broadcasters ill-timed affliction getting in the way, even for just a few moments, for what we all came here for – the Olympic Games.”

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PREVIOUS, 12:02 PM:  “Our long nightmare is over,” NBC Olympics EP Jim Bell said this morning to kick off a phone conference call with the media in re Bob Costas’ return to the network’s primetime Sochi Olympics coverage. Costas returned to the NBC Olympics studios at the International Broadcast Center in Sochi, Russia, on Sunday to prepare to resume his primetime and late-night hosting duties tonight. Costas is better, but his eye condition still is  noticeable and he will wear glasses again. On today’s phone call, Costas joked of his eyes, “It won’t look as bad as it did the last night I was on the air, and probably it will look better 10 days from now — but the Olympics will be over.” His absence, since last Tuesday, ended his streak of 157 consecutive appearances as NBC’s Olympics anchor in primetime; it was the first time since 1988 that Costas had not hosted the primetime coverage.

(Bell’s Costas nightmare may have been over, but another had begun that trumped Costas’ Twitter-trending eyes. In this nightmare, the press blasted NBC for an interview in which Bode Miller took so many questions about his dead brother that he doubled over and wept after winning the bronze in the super-G. That interview came on the heels of Vieira’s questions to American skeleton racer Noelle Pikus-Pace about a miscarriage she suffered a few years ago, which came on the heels of a question an NBC reporter asked American Olympian Katie Uhlaender, right after she missed securing a bronze medal by 4/100ths of a second, as to how her deceased father would have felt, watching her performance. The Costas call quickly went off the rails when Bell got asked whether he thought NBC had gone too far with the line of questioning in which Olympic athletes personal tragedies were probed and whether he was re-thinking the strategy. But before that, Costas took some questions about his eyes, and coming back to the air tonight.)

During the six days he was off the air while doctors treated his double eye infection, Costas said he spent time in a darkened hotel room, later ventured downstairs to the hotel restaurant to break the monotony, walked out onto his hotel room terrace to get some fresh air, and watched NBC’s Olympics coverage. “As days went by, I got progressively better,” he said, putting his “injury scale” at “about a 2″ out of a possible 10. .”It was the light sensitivity and blurriness that made it impossible to go back on the air.”

Costas said his thought during his involuntary absence was not “Oh my gosh, I’m missing these nights on the air” but rather, “My thought was all my colleagues and friends who worked so hard – many of them harder than I worked, many of them 18 and 20 hours a day — I want to hold up my end of it.” He described his role at Sochi as “not necessarily the most important part but the most visible part.” He added, “I knew Matt and Meredith would, and did, handle it capably.

Lauer last week pulled double duty for three days, co-anchoring Today from Sochi while also filling in for Costas in primetime; he also filled in last night. Vieira stepped in Friday and Saturday, becoming the first woman ever to anchor NBC’s Games coverage in primetime.

Asked his thoughts on the media coverage of his eyes, Costas said, “I only have a fraction of a sense of the way it was covered” and that is only “aware generally, from friends, that this was viral, literally and figuratively.” He added: “I don’t feel comfortable having anything other than the work itself what people are talking about, but sometimes it’s unavoidable. … I’ve often said if someone were to go on the air and recite the Gettysburg Address from memory but wore a bow tie when they usually don’t, people would say, ‘Hey, what’s with the bow tie?’ That’s the world we live in.”

Costas was last seen on the air a week ago, telling NBC’s Mary Carillo as he downed what was billed as a good-ish dose of  the Russian booze, “My eyes can’t get any redder” and predicting, after polishing off his drink, “Tomorrow morning I’ll be lying on a curb in Minsk.”

Last Tuesday, Costas became the latest casualty of treacherous conditions of the Sochi Olympics, announcing on Today he would sit out that night’s primetime coverage  after the infection in his left eye spread to his right. Costas started his Olympics coverage for NBC the previous Thursday with his left eye inflamed and sporting glasses. Five days later, Costas’ double-eye infection had become one of the Sochi Games’ talking points — and a Twitter trending topic. Costas phoned in to Team Today last Tuesday to announce he would not host the network’s coverage that night because his eyes had gotten even worse than the previous night, when they looked plenty bad enough. “I might as well be playing Marco Polo,” he said. “I have no idea where I am.”