The inactive defensive players for each San Francisco 49ers game differ from week to week. For example, linebacker Aaron Lynch finally got into a game this past Sunday against the Houston Texans while defensive lineman Ronald Blair, who had been active, was not.

A lot of the defensive personnel decisions depend on the team's needs against any given opponent. Defensive coordinator Robert Saleh explained on Thursday.

"First and foremost, it always starts with the opponent and what they do best," Saleh told reporters. "Whether we need to get big or smaller is the first thing (in the) run game, pass game. With regards to the overall roster, we feel good where it's at with the D-line.

"It's unfortunate there are some healthy scratches in there that deserve to be playing like -- love what Ronnie Blair is doing and not having him up was more of, 'Let's get Aaron and Tank [Carradine] out there to see what they can do. Same thing with [Leger Douzable].

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"So just giving people an opportunity to go out there and put tape out there. They're deserving. They work their tails off so sometimes it's just a matter of guys are working really hard and they deserve an opportunity to play.

"What's cool about this team and where's it's going is it's becoming a very selfless team in regards to those D-lineman are all really pulling for each other. Yeah, I'm sure a guy like D.J. Jones is frustrated that he can't be active but he's pulling for the guys who are active and vice versa. Douzable not being up last week pulling for Lynch and Tank to do very well.

"So, that part with the D-lineman having each other's back, that part is cool and that's really what it's coming down to is that there are some healthy scratches that can be on the football field. But, again, it's giving guys opportunities to play. Who deserves it with their practice habits?"