What do the Seahawks want in an offensive lineman? It’s a tough one. They’ve pretty much gone after everything since Tom Cable arrived in Seattle:

— The converted defensive lineman, brimming with athleticism (Sweezy)

— The every-man, blue collar ‘no thrills’ type (Moffitt)

— A hulking, massive run blocker with length and power (Carpenter)

— The street fighter with a wrestling background, full of potential but raw (Britt)

We do know they like tackle converts or at least players with experience playing multiple positions. Size and length is attractive but not exclusive. There seems to be a lot more wiggle room on the O-line than other positions.

Cable picks his guys and uses a broad canvas.

I do think they maintain certain ideals, however. They run a zone blocking scheme with a power element, meaning size is as important as mobility. It’s not a small O-line like you traditionally see in the ZBS. Across the NFL teams are searching for athletic linemen to counter the influx of incredible athletes playing defense in college.

Seattle needs to fill two holes at center and left guard. I suspect it’d be counterproductive to move Britt inside. You’d be adding to the upheaval. Instead of two changes to the O-line you’ve got three. If Britt doesn’t work out at guard you wasted a year of development at right tackle and run the risk of a musical-chairs situation up front.

Draft a guard. Draft a center. Get to work.

The options in this draft class practically encourage that sentiment.

You can pinpoint an appealing prospect with every Seahawks pick between rounds 2-5. We’re talking possible week one starters too. After all, Seattle started J.R. Sweezy as a 7th round rookie project in 2012. That didn’t end well but no rookie drafted in this class is likely to face the same level of adjustment (switching from defense to offense in a matter of weeks).

At #63 I still believe Colorado State’s Ty Sambrailo makes a ton of sense. When I spoke to Tony Pauline last week he insisted he won’t be available in round three and would provide terrific value in the late second. For me he’s a plug-in-and-play guard for this scheme. He has the size to fill Carpenter’s massive void, the mobility for the ZBS and the desire to get to the second level. He’s not the finished article but he has as much upside for this scheme as anyone in the draft. I suspect the Seahawks like prospects that aren’t considered the finished article — they want room to grow and develop within their setup. Sambrailo fits the bill as an athletic tackle convert.

Guard and center are the biggest needs right now — but that doesn’t mean the Seahawks have to go that way with their first pick. I suspect they’ll be enamored with receiver Tyler Lockett. He’s a gritty character guy with superb playmaking ability. He just knows how to get open, consistently makes big plays and has underrated lower body power and spirit. He’s also a week one punt/kick returner — carrying added value. If he’s there at #63 he might be difficult to pass up. That puts the O-line focus on the middle rounds.

I think the Seahawks would be quite comfortable in that scenario. Lockett is a terrific player with instant impact potential in the return game. The Seahawks have gone early and often on the O-line since 2012 and yet their biggest success story so far is the 7th rounder spent on Sweezy. A cluster of athletic scheme fits in the mid-to-late rounds open up the possibility of passing on a Sambrailo (for example) at #63, even if it’s an attractive option at the biggest need position.

This piece by Zach Whitman for Rotoworld highlights the more athletic linemen in the draft. You can see some familiar names on his list.

Ali Marpet is, according to Whitman, the most dynamic athlete among offensive linemen in the 2015 draft. He notes: “If a player is in the 50th percentile, they rate as a perfectly average NFL athlete.” Marpet is in the 96th percentile. He might be raw and untested against top-level college opponents — but he’s a heck of a ball of clay ready to mold. He’s also an ascending talent. The small-school aspect will be off-putting to some and for that reason he maybe lasts a little longer than he should. It equally won’t be a shock if he goes in round two.

Almost every week we learn something new and interesting about the guy. Today it’s this: “Ali’s father, Bill, is an Emmy-winning director and cinematographer who is considered the leading producer of fashion videos in New York.”

Who knew?

It might be unlikely, but a double dip of Sambrailo and Marpet would offer a real injection of upside, size and athleticism to Seattle’s interior line. You’d be looking at the most athletic interior in the NFL when you throw Sweezy into the mix.

As you run down Whitman’s list you notice Laurence Gibson at #4 — a legit later round option. He has one year of tackle experience at Virginia Tech but exploded at the combine with size, length and athleticism. He’s one to watch for sure as a tackle project — especially if Seattle has to consider moving on from Russell Okung in the future.

Rob Crisp is a little further down — a player we’ve talked about a lot since the start of the college season. He’s enormous in terms of length and he’s a plus athlete. For me there’s no reason to think he can’t play left tackle at the next level. He shut down Vic Beasley in a way nobody else did in college football. He’s a tremendous, highly underrated prospect.

San Diego State’s Terry Poole tests well and has genuine guard/center size with tackle experience in college (boxes ticked). He’s big but has a nice squat frame. You could easily see him enjoying a long career at guard.

Mitch Morse is number five on Whitman’s list. A close friend of Justin Britt, Morse is highly athletic and also has experience at tackle. He has identical size to Max Unger and could kick inside to play center as a fourth round project. Stranger things have happened. He’d also make a nice option at guard.

We ran through some of the center prospects the other day. The options are deep and rich:

B.J. Finney — really solid if unspectacular, has the wrestling background Tom Cable likes

Andy Gallik — superb second level blocker, street fighter, lacks ideal size

Hroniss Grasu — ideal zone blocker, big time leader and technician

Shaq Mason — drive blocker although hard to project working in the triple option

Max Garcia — some don’t like him but I do as a project, did well at Senior Bowl, hit and miss and not the most mobile.

You could realistically get Finney, Gallik or Grasu in the middle rounds, with Mason and Garcia available later on. There’s really no reason why any of the first three names cannot start in 2015.

Filling spots on the O-line with cheap rookies will be vital as the team manages it’s cap situation and begins to pay more of the storied veterans. You could be paying a second, third or fourth round salary to a starter for the next four years. That’s big.

It’s probably one of the main reasons the Seahawks are busy adding veteran defensive line depth having already added Cary Williams and Will Blackmon to the secondary. The best depth and value in rounds 2-5 is going to come on the O-line and at wide receiver. Getting five players at both positions in the middle rounds shouldn’t be ruled out. They’ve got the picks.

Quite frankly if they can’t find a couple of guys to fill these two most pressing needs on the O-line, it’ll be an upset. The sheer depth of options and the vast quantity of picks equates to a perfect storm. They select four times between the end of the third and the close of the fourth. Even if neither hole at guard or center is filled at #63 because they’ve taken a prospect like Lockett, they’ll still have many opportunities to feel very good about the situation up front.

Meanwhile, it’s only a small update — but we’ll take it. Jim Thomas from the St. Louis Post-Dispatch isn’t expecting any imminent news on Stefen Wisniewski.

And finally — the compensatory picks were announced today. Seattle received the four we expected. However, Breno Giacomini only netted a 6th rounder and not the projected 5th rounder. It means they gain one extra fourth, a fifth and two sixth’s — taking the overall total to eleven picks:

1st round — Jimmy Graham

2nd round — original pick

3rd round — original pick

4th round — from New Orleans (Unger)

4th round — original pick

4th round — compensatory pick

5th round — original pick

5th round — compensatory pick

6th round — from New York Jets (Harvin)

6th round — Marcus Burley

6th round — compensatory pick

6th round — compensatory pick

7th round — original pick