As you should already know, this weekend the Lions travel to Minnesota for a NFC North rivalry game with the Vikings. The two teams always seem to play each other very close, and then one team pulls away in the last remaining minutes. Although the Lions haven't won against Minnesota in quite a while, they always are within reach of doing so.
Since the Lions travel to Minnesota, and are playing on the road, there may be a scheduling conflict that could arise. The Vikings share the Metrodome with the Twins, and if the Twins took their American League Divisional Series to a fifth and deciding game, the two teams would have a home game on the same day. Because the playoffs are obviously a greater deal than a regular season game, the Twins would get the home game and the Vikings would have to come up with a solution.
The two logical ways that the Vikings could work around this is either moving the game to Monday night or switching the home and home series around so the game would be in Detroit instead and then at Minnesota later on in the season. The second option is not likely to happen as the Lions have already stated that they wouldn't do it because it would make the last four out of five games of the season on the road.
The only option that is left now would be to move the game to Monday night. If that happens, reportedly FOX would not allow ESPN to do another doubleheader like in the opening week, but instead make the game apart of a regionalized telecast. The specifics of how all of the switching around for television would work is not known, but if FOX lost a game and ESPN gained one, I'm sure some conflict would come about.
Remember, this is all just a big if. The Twins are down 0-2 in their series to Oakland, and have to win both of their next two games at the Athletics to stay alive for Sunday. The chances aren't very high that this scenario will pan out, so I would expect the game to be played on Sunday as originally scheduled.