Savannah Guthrie made her official debut as Matt Lauer’s co-host on NBC’s ‘‘Today’’ show Monday, admitting to some anxiety and nerves in her new role in NBC’s attempt to steady the wobbling ratings of the show in recent months. The 40-year-old Guthrie, NBC’s chief legal analyst, said she was honored to have one of those rare jobs ‘‘you can describe as fun and actually mean it.’’ Guthrie has also co-hosted the four-hour ‘‘Today’’ show’s 9 a.m. hour for the past year. But the 7 a.m. to 9 a.m. stretch with Lauer is the main event, where it directly competes with morning news shows on ABC and CBS. ‘‘Good Morning America’’ on ABC in the spring ended a streak where ‘‘Today’’ won in the ratings for every week back to 1995, and the programs have traded victories ever since. For the last week of June, the shows finished in a dead heat among viewers in Nielsen’s numbers! And Monday, GMA debuted their PM version of the show with Good Afternoon America! Take a look below at the preview before the show!