How big is Seattle’s game against the Rams? Probably the difference between a home playoff game and a road trip — and certainly a major factor in the race for home field in the NFC playoffs.

This is the second straight year the Seahawks have hosted the Rams in Seattle in Week 5 after playing at Arizona in Week 4. Last year, the 33-31 home loss to the Rams was the difference between 10 wins and 11. If the Hawks had flipped that game and beaten the 49ers in Week 15 (rather than lose in OT), they would have been at 12 wins and won the division thanks to a better conference record than the Rams. That would have made them the NFC’s third seed, hosting the Eagles in the wild-card round instead of going to Dallas.

And while we are doing what-ifs: If the Hawks had beaten the Saints in Week 3 this year, rather than handing the win to New Orleans, they would be going for 5-0 and early control of the NFC this week. Instead, they are just trying to stay in the mix in both the division and conference while flipping the script on a Rams team that has beaten them three straight times and won the division the past two years.

The Seahawks have not done enough yet this season to be considered one of the NFC’s top teams, even though they are among seven three-win clubs. Football Outsiders, Five Thirty Eight and Vegas all rate the Hawks the third-best team in their division — perhaps because the Hawks’ wins have come against three teams that are an aggregate 1-10-1.

So when Pete Carroll calls this one a “championship opportunity,” he means it more than usual. This is a big validation game for the Hawks.

At this point, Vegas expects the Rams (3-1) to win 13, the 49ers (3-0) 11 and the Hawks 10 (including this one against the Rams). Five Thirty Eight projects Seattle at 10 wins, too, with a 49 percent chance to make the playoffs and 25 percent to win the division (the Rams are at 40 percent and the 49ers at 34 percent for the division).

Carroll likes the idea of the NFC West having three strong teams again. “It’s really important for us in that every week you have to perform at your best to stay abreast of the other teams,” he said. “That’s good for you; it makes you better. It will bring out the best in us.”

They will need their best to beat a Rams team that has scored 111 points in its three-game winning streak against the Hawks. Like Seattle, the Rams haven’t looked great yet this season, but they still are 3-1 and averaging 29 points — they lost 55-40 to Tampa Bay last week.

“We have not been able to do better against them than anybody else (has),” Carroll said. “They’ve been on a great run, and they’ve started off the season in great shape. … We’re going to have to figure out a way to slow down an offense that put up 600 yards last week and 40 points — in a game they lost.”

Last year, the Hawks lost two shootouts — 33-31 and 36-31. After dropping a 33-27 game to New Orleans a couple of games ago, the Hawks are a paltry 3-14 when their opponents hit 30 points. So you’d think the onus would be on Seattle’s developing defense to keep L.A. under 30.

But maybe Wilson is ready to win a shootout, like he did against MVP Patrick Mahomes and Kansas City late last season (after the losses to the Rams). Wilson is playing the best ball he has ever played early in a season — perhaps at any point in a season.

“I think he’s off to his best start ever,” Carroll agreed. “I don’t know what it looks like numbers-wise, but I don’t think he’s ever been more accurate than he’s been or more consistent and in command of everything. I think he’s off to a great start. I don’t care how big the numbers are – I’m not talking about how many yards or whatever – just his play has been really sharp.”

Brian Schottenheimer said the offensive tempo has improved because he and Wilson are in sync.

“If you look at it closely, our ability to get in and out of the huddle this year is better than it was last year,’’ Schottenheimer said. “A big part of that is him hearing me and knowing what I’m saying.”

Wilson said he is “locked in and ready to roll.”

He might get plenty of chances, based on how Jared Goff is playing. In the past two games, the Rams’ passer has turned the ball over seven times. If the Hawks can get two or three while protecting it themselves, they might (a) keep the Rams under 30 and (b) give Wilson a shot to outscore the Rams like they couldn’t last year.

In the Week 5 meeting last season, Seattle’s inexperienced secondary was ripped apart. That unit is still in flux, but Tre Flowers is a year smarter and Shaquill Griffin is playing great football; Seattle’s three linebackers can do everything (K.J. Wright and Mychal Kendricks didn’t play in this game last year); and, of course, the Hawks have Ziggy Ansah and Jadeveon Clowney. So, while it is still developing, this is a more talented unit.

Add to it this mentality: The Seahawks have turned into winners again. They are 9-3 since they last played the Rams — a 36-31 defeat in L.A. in Week 10 last season. Their losses have been unique: an overtime dud against San Francisco, an offensive coaching snafu in the playoffs against Dallas and a mistake-filled loss to New Orleans this season.

The Seahawks are so focused on this game. Their thoughts were on the Rams right after they beat Arizona — the entire locker room glued to the TV and then erupting as the Rams lost to Tampa Bay. They started watching film of the Rams on the flight home and thus were able to install a week’s worth of game plan in two days. And it looks like every player (except maybe Ethan Pocic) will be available, so Carroll can field the best iteration of his team.

“They’re going to challenge us in every way,” Carroll said, “but we need this kind of challenge.”

And you can sense these Hawks are going to rise to it and give the Rams the best game they have gotten from Seattle in a couple of years.