What happened to the 9'er's Defense the last four weeks?

Just looked up the 9're's record and noticed how they were giving up a LOT of points there for a lolng while ( the first 7 games of the season) and then put the brakes on the scoring against them the last four games. So, Whot'Hapin? Did someone get fired or hired or were there injuries that healed and they got players back or did someone step up after someone else got injured?
Seems like something HAD to have happened to turn them around but I just don't know what! I sure hope our OC knows what happened and can tap into that leaky defense they had at the beginning of the season so we can roll it up on them!

I feel pretty confident that our Defense can handle Gore and the 9'er's "O"-line. We have been playing with enough emotion and quickness to accomplish good things and take advantage of whatever they give us when we're on Offense and for our Defense to take control of their game.

Going into the Dome, with Coach Payton urging the team to "Take Care of Our Home!", this may be a game where the TEAM can hit on all cylinders and make a nice statement!