It's no surprise that these two teams have quickly developed a heated rivalry.
The Niners defeated the Lions last season, and it left a bitter taste in their mouth. Actually that's an understatement. Detroit had a chance to win but failed, Jahvid Best was lost for the year and Jim Schwartz and Jim Harbaugh had their now-famous handshake.
Both teams can be as politically correct as they want; fans know the truth. They both want to kill each other.
The Niners are clearly the favorite. They dismantled the Green Bay Packers in Week 1, and their defense looks even better than last year.
The Lions shouldn't be overlooked though. Their offense can score on anybody and any time, and their defense isn't too bad either.
In order for the Lions to win, several players have to come through with big games though. Here are the players that will impact the Lions chances of beating the Niners the most.
* All stats in this article courtesy of ESPN.com