As the Seahawks get ready to open the preseason Thursday against Denver, most fans are itching to see rookie wunderkind D.K. Metcalf.

But we won’t see him play with Russell Wilson, because the starting quarterback will not play (a bunch of other starters will sit, too, Pete Carroll said Wednesday).

But there are a lot of other things to keep an eye on, starting with a defensive line that sure doesn’t seem like it will be ready for prime time yet — if ever this season.

There was cause for concern even before Frank Clark was traded, Jarran Reed was suspended and first-round pick L.J. Collier suffered a “rare sprain” that will keep him out for weeks (though he is out of his boot).

If Ziggy Ansah is not ready for Week 1 against Cincinnati, the Seahawks’ starting line would be something like Cassius Marsh, Poona Ford, Al Woods and Quinton Jefferson. That’s a pretty pedestrian bunch — and would easily be the worst starting quartet Carroll has had in Seattle.

This is the first time Carroll has not returned his top sacker from the previous season, with Clark and his 13 sacks dealt to Kansas City. Carroll had returned his top two sack guys every year from 2013 to 2017.

But the past two offseasons have seen Seattle drop its top four pass rushers, counting Reed’s looming six-game absence — and they have no sure-thing replacements for any of them.

Barkevious Mingo is perhaps the most intriguing player to watch this preseason. Can he fulfill the promise of his first-round draft status from 2013? Carroll oddly did not use him as a rusher last year, but — with the linebacker position now looking pretty stacked — Mingo finally gets a chance to show what he did in his early days in Cleveland.

Beyond that, as Carroll said, “This is an opportunity for the young guys. This is the game we dedicate to the rooks; it’s their first NFL game ever. … We’re going to play our young guys a ton. There will be some mixes in the starting lineup you’ll see right from the get-go. … We want to see if these guys can help our football team, and they can’t do it by just watching.”

Here’s the rest of what we will be watching at each position:

QUARTERBACK
State of the position: Geno Smith and Paxton Lynch have been battling to back up Wilson, who is using camp to get in better sync with Brian Schottenheimer and his new receivers. Smith, known as Genius Smith to autocorrecting smartphones, reportedly has the edge. He will start vs. Denver and will have an injury (thought to be a knee) addressed after the game. Carroll said he thinks Smith will be ready for the second game, which is 10 days after the first.
What we’re watching: Smith will start and Lynch could see a lot of time against the team that traded up with Seattle to draft him in 2016. Accuracy will be the first thing we look for from these guys.
Schottenheimer on the backup battle: “Ultimately, it’s going to come down to who can move the team and who can score points for us in the preseason.”

RUNNING BACK
State of the position: Chris Carson and Rashaad Penny and fullback Nick Bellore look like locks, leaving the rest to fight for two spots. J.D. McKissic seems like a good bet to claim one. C.J. Prosise has a sprained hip and won’t play. Rookie Travis Homer (quadriceps) won’t play either.
What we’re watching: Bo Scarbrough figures to get a ton of work and could take the lead on Homer for the final spot. Homer is more of a third-down option, while Scarbrough is a pounder. If Penny is in line to play the third-down role, Scarbrough could have a good shot.
Carson on Schottenheimer’s scheme: “He’s doing a lot with the running backs. He’s splitting them out wide, putting them in different spots around the field. He’s using us more in pass-catching than what he did in the previous year. It’s fun for us. … All the running backs have great hands; it’s good to see us finally be able to use (them).”

WIDE RECEIVER
State of the position: Jaron Brown is the favorite to start opposite Tyler Lockett, with David Moore leading for the third spot. Metcalf clearly is a lock as well, leaving one or two spots up for grabs.
What we’re watching: The rookies. Metcalf (oblique) was back at practice Tuesday and should play, and it will be good to get a first look at Day 3 draft picks Gary Jennings and John Ursua, plus 6-foot-5 UDFA Jazz Ferguson. Oh, and can Amara Darboh take advantage of his odd resurrection in Seattle and show he deserves a shot?
Schottenheimer on Brown: “We probably underutilized him last year. I probably did. … He does everything right. … There’s not a guy out there that I trust more than Jaron to do anything. … So selfless, so all about the team, great teammate, really good player that we expect big things from this year.”

TIGHT END
State of the position: Ed Dickson had knee surgery and is out 4-5 weeks, Carroll said. Will Dissly’s return from a torn patella tendon is one of the two biggest rehab stories of camp (along with Ansah), but he won’t play. Tyrone Swoopes was waived-injured and Jacob Hollister has a minor groin injury, which gives Vannett a better shot to stick around in his contract year.
What we’re watching: Not much. Vannett is the only healthy guy, but he is not likely to play much either. That leaves fifth-stringers Wes Saxton and Jackson Harris.
Carroll on Dissly: “We are going to hold Will in this game. He’s done beautifully. He had his best day since he’s been back just yesterday. He looks great, ready to go. But we want to wait. Again, we didn’t think Will would be this far along, so he’s way ahead of schedule. So we are just not going to push the issue now.”

OFFENSIVE LINE
State of the position: Other than Mike Iupati’s sprained foot, this unit is healthy and poised to be perhaps even stronger than it was in 2018. The top seven seem set — with George Fant and Jamarco Jones as the backup tackles — which would mean Ethan Pocic, Joey Hunt, Jordan Simmons, Elijah Nkansah, Marcus Martin, Jordan Roos and Phil Haynes are battling for the final two or three spots. Pocic, who needs a good preseason to stick, has gotten lots of time at left guard in Iupati’s place.
What we’re watching: Is Pocic still getting pushed around? How does Jones look after missing the 2018 season? Can Haynes challenge Simmons?
Brown on Germain Ifedi: “I think Germain Ifedi is going to have a really big year. Every year he’s improved. I think last year he took a big step. It’s all about confidence. The more confidence you have when you step on the field, no matter who your opponent is, you have a chance to perform well. And I think he’s gained more and more confidence throughout his career. I’m looking forward to seeing what he can do.”

DEFENSIVE LINE
State of the position: Pretty bad. Clark is gone, Collier is hurt, Ansah is questionable for Week 1 and Reed won’t be on the field for the first six weeks. So there is no proven pass rush, with Martin, Marsh and Mingo the top options. Rasheem Green needs to take a HUGE step (except he has an elbow injury). The DT rotation should be OK, with fan favorite Poona Ford and veterans Al Woods and Earl Mitchell. Former third-rounder Nazair Jones (battling a knee injury) seems to be on the wrong side of the bubble as preseason begins.
What we’re watching: Mingo is trying to make it as a pure pass rusher, a transition worth following. Green’s development (or lack thereof) will be a big storyline as well. And can Ford and the veteran defensive tackles improve the run defense?
Mingo said: “I came into this league to rush the passer. And teams I’ve been on before, they’ve had a different idea of what they wanted me to do. And that’s OK. It’s their team. They can play their players how they want to play them. But … I’m happy I get to go back and do it (rush the passer). I wish it would have been a little earlier in my career. But still, I’m just excited for the opportunity to go out there and just help the team.’’

LINEBACKER
State of the position: Not 100 percent. Bobby Wagner is sidelined after a minor procedure on his leg, and Cody Barton (groin) is unlikely to play. Austin Calitro should be a lock as Wagner’s backup again. Shaquem Griffin is on the bubble and will need to show vast improvement if he is going to stick again.
What we’re watching: K.J. Wright and Mychal Kendricks might finally play together for the first time — though it will be brief if it happens. Griffin will get a chance to show all of the savvy he gained over the last year, and Calitro and Ben Burr-Kirven will play a bunch with Wagner and Barton out.
Carroll on Wagner’s procedure: “He’s done it a couple times before. It’s been successful for him and it’s helped him out over the years, so it just felt like it was time to do it …”

SECONDARY
State of the position: The safety battle probably won’t really start until the second preseason game, since Lano Hill just came off PUP (and won’t play), and Marquise Blair has barely done much either. The corners are set, except perhaps the nickel spot — where Jamar Taylor might push Akeem King. Unless Hill or Blair (or another safety) gets hurt again, DeShawn Shead probably faces an uphill battle for a second stint in Seattle. Shalom Luani might actually be favored to make it over Shead.
What we’re watching: Blair has a long way to go, but it will be good to see his touted athleticism (Carroll said he will play a lot). Tedric Thompson can take a big lead in the race with Hill to start next to Bradley McDougald. Does rookie Ugo Amadi have a shot at safety? What does Shead look like these days?
McDougald on Blair: “Being a rookie in a new system, he has things to work on. But, just athletic-nature-wise and a nose for a football, I would say he has it. He showed up in OTAs, made a couple splash plays, and the same has led over to camp. So, I’m happy for his growth. I want to see him keep growing and keep building. We’ve got things to work on, but for a rookie … in his first training camp, I would say he’s off to a great start.”

SPECIAL TEAMS
State of the position: The three main spots are now secured for at least the next three years, after Tyler Ott signed a four-year extension. It sounds like Jason Myers has been great in camp, and All-Pro Michael Dickson said last season was not even his best football year.
What we’re watching: Myers for consistency, Dickson for fun and the kick and punt returners. Tyler Lockett said he expects to do both, as he largely did last year. But McKissic and Penny — maybe others (Moore?) — seem likely to factor in.
Brian Schneider on Dickson: “He has a lot of high goals; his work ethic is unbelievable. … He is aiming to be the greatest ever.”