The one thing giving the 49ers defense a chance

This was huge.

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If you want a quick glance at how long an NFL season is, look no further than the San Francisco 49ers' safety room. During the first four weeks of the season, it was the clear weakness of the defense and the unit that everyone was picking on. As the 49ers head into the playoffs, you can argue this is the only position with some stability. 

San Francisco 49ers safety room leads the defense

This is not some coaching marvel, though it did take a few tough decisions by the coaching staff. Still, rather than the players who started the season progressing into a strength, the 49ers simply swapped them out and upgraded.

The team started the year with Jason Pinnock and Marques Sigle. Sigle is a sixth-round rookie and went from a starter to completely inactive. Meanwhile, Pinnock was pushed aside by both New York teams before the 49ers gave him a shot. He plays dime here and there, but the 49ers are usually worse off when he is on the field. 

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In their place are Ji’Ayir Brown and Malik Mustapha. Brown was great in that dime role and has been better than Pinnock as a starter as well. His two interceptions helped deliver San Francisco a win on Monday Night Football against the Carolina Panthers. 

Malik Mustapha returned at about the quarter point of the season from an injury last year. Since he has been in the lineup, he has been one of the best 49ers defenders. He led the team in tackles against Carolina and was a defensive stud. 

Simply put, the 49ers do not win this game with Pinnock and Sigle still starting. This is a huge development for the 49ers. Both Mustapha and Brown are still young and progressing. Mustapha is still getting back to full strength from his injury last year. 

San Francisco is obviously not going to have an elite defense, but if the offense can be competent, the defense just has to stay above the bottom of the barrel. Having one posiiton group that features impact players is what keeps you away from a floor. 

It took a little bit of good health for once, and the it took the team assessing the roster and making a smart change to the lineup. Those are the signs that give 49ers fans faith that the defense can still turn things around long enough for a playoff run.