When the Seahawks head to Santa Clara this weekend to face the 49ers, it will be the second meeting between the two NFC West squads in the past six weeks, but despite the fact that these two teams faced off fairly recently, both sides will look considerably different at several positions.

Some of that is injury related for both teams, but for the Seahawks, and their defense in particular, the change has more to do with decisions made by Mike Macdonald and his coaching staff than it does the team's health.

While every coach will preach that practice reps matter, and that everyone is competing for playing time, significant lineup changes in the middle of a season are far from the norm in the NFL.

Yet when the Seahawks face the 49ers on Sunday, they'll have two new starting linebackers since that previous meeting, having traded Jerome Baker, along with a draft pick, for Ernest Jones IV, and having earlier this week waived Tyrel Dodson, leading to a likely start for rookie Tyrice Knight. At safety, Coby Bryant has taken over a starting job following an injury to Rayshawn Jenkins, and has played well enough that it's hard to see him not having a significant role even when Jenkins is able to return. And at cornerback, Josh Jobe, who was on the practice squad having yet to see game action for Seattle when the two teams met in October, has now played a big role in the past three games and earned a spot on the 53-man roster. And even with the Seahawks getting back to full health at cornerback, Macdonald said Jobe will likely be the team's third cornerback, joining starters Devon Witherspoon and Riq Woolen on the field in nickel packages.

While making in-season changes isn't always comfortable—after all, someone has to lose playing time for another player to earn it—the way players like Knight, Bryant and Jobe, as well as receiver Cody White, have earned their bigger roles on the team is a perfect illustration of what Macdonald is preaching to his team about everything mattering, not just on gamedays but in the work done Monday through Saturday leading up to games.

"We want to be program built on development and bringing guys along—you earn your opportunities," Macdonald said. "And then we want to celebrate it when you go out there and you show what you can do. We've had several examples of that, and hopefully that sends a message to the rest of the guys that that's how we want to operate. That's where you earn everything is just day-by-day, the meeting room, walkthroughs, how you go about your business, the type of person you are, all that stuff. We're trying to make people grow in all aspects of their life."

Jobe, a former undrafted free agent who spent the past two seasons with the Eagles, has four passes defensed, 17 tackles and his first career interception in the past three games since first getting his shot due to injuries at cornerback. He sees his success, and that of other backups turned starters, as an indication of the level of trust coaches have in their players.

"We have a great environment for the team," Jobe said. "The coaches, they trust all the players. They trust us to play great and play to the same standard as the other guys."

Bryant, who was the starting nickel corner as a rookie before losing that job last season due to both injuries and the addition of first-round pick Devon Witherspoon, began transitioning to safety last season. It was a move he didn't embrace at first, but over time he has grown into that role and is thriving this season, frequently earning praise from Macdonald while showing up as a playmaker on Sunday.

His promotion, as well as those of teammates like Jobe and Knight, "says a lot," Bryant said. "That we're willing to work, that nothing is given to us, and once you get the opportunity, you take full advantage of it."

And for Bryant, the key to working his way back into a more prominent role on defense was the work he put in every day.

"Just competing, doing the little things right, and when you do get the opportunity, you take full advantage of it—special teams, practice, and obviously in the game too," he said. "There's always work to be done."

Knight, meanwhile, is in line to make his third start of the season, having started two games earlier this season in place of an injured Jerome Baker. Baker's return to the lineup, and later the addition of Jones, meant a backup role for Knight, a fourth-round pick out of UTEP, for the past four weeks, but like Bryant and Jobe and other players who have fought their way up the depth chart, Knight found ways to make an impression even with limited reps on gameday.

"Everybody should know that everything we put on tape, coaches are going to watch," Knight said. "So everything we do in practice, do it to the best of our ability, and eventually they'll take notice."

And as Macdonald noted last week, seeing a player like White make big plays after being elevated off the practice squad, or seeing Jobe and Bryant thrive after taking on starting roles, or seeing Knight earn a promotion, those moments are among the best parts about being a football coach.

"It's probably the best part of the job when you see guys grow, and what gets you hooked is when guys do stuff one day that they haven't done the day before, to see hard work really pay off," he said. "I mean, these guys, they work extremely hard and a lot of them were working in the shadows to help the rest of the team. We had a crew come visit us last week and one of the people said that they wanted to be a force multiplier for their squad, and I felt like some of these guys that are really working for our teams are force multipliers for us."