While the 2021 NFL schedule has been finalized and every team knows the week they are playing each opponent, 10 teams don't know the exact date of the game they will play. This schedule anomaly occurs in Week 15 of the season, the first of three weeks the NFL will have Saturday games. 

Five matchups have the potential to be "flexed" into the Saturday slate on Dec. 18, which is Week 15 of the season. In Week 15, two of the five matchups currently designated as TBD will be played on Saturday with the remainder to be played on Sunday. Specific dates and start times for these designated Week 15 matchups will be determined and announced no later than four weeks prior to game day, so don't expect these matchups to be set until November.

The NFL is taking advantage of a Saturday window to showcase games with potential playoff implications or games that could involve a playoff race. Last season when the league "flexed" these games, two of them were shown on NFL Network and one was exclusive to streaming. The only way to watch that game is by streaming it through Amazon Prime or Twitch. 

So why is that the case? Amazon was given a standalone game as part of a new streaming deal the the streaming service signed with the NFL back in April 2020, part of the company's contract that allows them to stream Thursday games through this season. Amazon will take over as the exclusive home of "Thursday Night Football" starting next season, signaling every game in the TNF package will be on the streaming service. Games involving the teams in the local markets will get to broadcast the game over-the-air, similar to the Amazon exclusive game in 2020. 

Last year's game was a CBS production, but it remains to be seen if Amazon will test its own production telecast for the exclusive matchup. One of these five matchups will be heading to Amazon, so be prepared if your team is called (15 games are coming to Amazon starting in 2022). 

Here are the five Week 15 matchups that don't have a set date and time. Remember two will be played on Saturday and three on Sunday: