Since the current incarnation of the Seattle Seahawks began their ascent in 2012, general manager John Schneider has said his goal is for them to avoid being a team that would quickly “cruise into” contention and then almost as quickly “cruise out.”

In other words, he wants to avoid a similar situation to the team they will play today, the San Francisco 49ers. They are in rebuild mode after a three-year run as one of the NFL’s better teams.

The backslide began last season when the 49ers went 8-8. Now they appear fully headed down the mountain in their first-year under coach Jim Tomsula, who took over for Jim Harbaugh and who seems destined to become another example of the inherent difficulties of following a legend. (And maybe coaching four years isn’t enough for Harbaugh to earn that label, but his 44-19-1 record gives him a .695 winning percentage that is fifth-best in NFL history.)

San Francisco’s route from 6-10 in 2010 to reaching the Super Bowl in 2012, then to what now is the NFC’s third-worst record is proof of how quickly things can change in the NFL.

Consider that the 49ers’ projected depth chart for today contains just four starters who also started the Super Bowl loss to the Baltimore Ravens — left tackle Joe Staley and left guard Alex Boone on offense and linebackers NaVorro Bowman and Ahmad Brooks on defense.

Another, quarterback Colin Kaepernick, had been demoted to the backup job before being placed on injured reserve Saturday.

As is no surprise, the tally isn’t a whole lot different from the 49ers team that almost beat the Seahawks at CenturyLink Field the next year in the NFC Championship Game — nine starters remain from that game, not including Kaepernick.

Last summer, a popular tweet showing the changes in the 49ers’ depth chart from the Super Bowl loss to training camp quickly was favorited and re-tweeted, many seeming to view it as a condition unique to the 49ers. FootballPerspective.com, though, was quick to note, that a couple of other recent Super Bowl winners had similar turnover. The 2011 Giants, for instance, had just three full-time starters remaining three years later, one of whom was quarterback Eli Manning.

Similarly, the 2009 Colts, who lost to the Saints, had just five starters remaining three years later.

And, well, hide your eyes maybe, but the Seahawks already have just 11 starters remaining from the starting lineup of their Super Bowl win over Denver, though one caveat is that Michael Bennett and Cliff Avril were not considered starters. Add them, and it is 13.

Still, change is change, as players and coaches have taken to noting with increasing frequency in recent weeks as the losses have piled up and media and others have come looking for answers.

“I think if you’re truthful, you know that every June and July starts a new life, a new team,” Seahawks offensive-line coach Tom Cable said this week. “So you have to make out of it what you’re supposed to.”

It’s Cable’s group that has undergone the biggest transformation, with just two starters remaining from the Super Bowl in February in left tackle Russell Okung and right guard J.R. Sweezy. Throw in the departure of tight end Zach Miller, and the Seahawks have seen turnover in four of the six main blocking positions, turnover forced in part by the complications of managing the NFL salary cap and having to find money at one spot to pay players at another.

The 49ers and Seahawks, though, both appeared to have one big advantage at the time of their first Super Bowl — a young quarterback not making much money. That changed for the 49ers in the summer of 2014 when they signed Kaepernick to a deal that includes a salary-cap hit this season of just over $15 million, up from $1.3 million in 2013.

The Seahawks, likewise, had to make a heavy investment this summer in Russell Wilson who went from making less than a million a year to averaging $21.9 million, the knowledge of which helped restrict the team’s offseason activities to mostly re-signing some of their own players. (They also made the Jimmy Graham trade but had to send off center Max Unger to make it work under the salary cap.)

The Seahawks, despite entering today just a game ahead of the 49ers in the standings, still appear closer to the top than the bottom of the NFL. But the 49ers have shown anew it is a distance that can be traveled all too quickly.