NBC often mixed their commentator groupings for 2016. Under league contract, Al Michaels and Cris Collinsworth called all of the games in the "Thursday Night Football" package that aired on NBC along with most Sunday nights. In general, Michele Tafoya served as sideline reporter for Sunday games and Heather Cox for Thursday games, with both sharing duties through the playoffs. Mike Tirico called play-by-play for secondary games in Weeks 15 and 16, and filled in for Michaels for "SNF" assignments in Weeks 11 and 12. The NFL waived its contract requirement for the 2017 season, allowing Mike Tirico to call all games on Thursdays, while Al Michaels remained on Sundays.