Sizing up the 2015 Raiders

The Raiders upgraded on about every front this offseason. Coaching, fitness and diet regime, roster and facilities. But the team remains enigmatic as players prepare to report to training camp in Napa Thursday . Here are a few things fans should keep an eye on:

Pass rush

The Raiders added depth along the defensive line this offseason, but the focus was on run-stopping instead of pass rushing. An understandable move, given as how the Raiders couldn’t stop a spider from getting loose into the secondary, though it’ll be interesting to see how much pass rush they’ll actually have with these moves.

Mario Edwards Jr., who the Raiders drafted in the second round this year, provides one part run stop, one part pass rush, but doesn’t seem too talented at any one aspect.

He’s a developmental player with solid upside, but a roll of the dice all the same.

Khalil Mack is instant pressure on the quarterback, even when he’s in coverage, but it’s difficult to predict that being a huge enough presence.

Clive Walford

Mychal Rivera has had some successful days as a young tight end in Oakland’s offense, but rookie Clive Walford (Univ. of Miami) is twice the athlete Rivera is, and his upside is there with Zach Ertz and Tony Gonzalez.

Even his own teammates are surprised by Walford’s speed, which is deceptive, and he has the blocking prowess to earn first team reps in week one.

But the nuances of NFL football make it difficult to earnestly predict a breakout rookie season. Is Walford mentally sound enough to make it on day one? Can he learn to exploit weaknesses that quickly?

This is often the reason why rookie tight ends don’t do a whole lot right away.

What Walford has going for him, though, is a lack of cover linebackers in the AFC West. In division games, Walford should feast, as Rivera has. But in others, it’ll be a coin flip at best.

Derek Carr and vertical passing

Some fans will read this and consider clicking off, but the Raiders were terrible throwing more than 20 yards downfield last season, and it wasn’t all about the receivers.

Carr’s 71 attempts became only 15 receptions, a 23.9 percent completion rate with only two drops factored in. Carr was fifth in attempts of such plays, yet ranked dead last in accuracy.

It’s fair, to some degree, to place some fault on a leaky offensive line and meddling receivers. Some blame can also be aimed toward game situations that dictated the deep pass, with defenses expecting it and doing everything to stop it.

But that’s where it ends. In the big scheme, Carr simply wasn’t very efficient.

This season will be the biggest of his career with the Raiders — he’ll need to show an ability to throw deep, or the team might continue their quarterback search. The raw numbers, as is often the case, don’t tell the whole story.

Carr can throw the ball with touch, accuracy, and velocity, and can do it all day. It’s seen in practice, even with a simulated pass rush and coverages. But he has yet to prove it on Sunday. His success moving the ball downfield will be paramount to the Raiders’ short term future, and Oakland can’t be playing from behind from the first quarter on.

Carr’s true grit will be tested this season, a solid-looking defense to keep things honest, and a terrific receiving crew. But it’s still a 50-50 proposition.

Right side of the line

The right side of Oakland’s offensive line is probably going to need some work in the next offseason or two. Unless tackle Menelik Watson kicks things into gear, which is possible, since he’s still relatively new to football.

Or, Jon Feliciano proving that the world was wrong about him, grading well into the fifth round or later by media scouts. But only one scenario, if either, is likely to happen. And even then, it’s not a bettor’s’ bet.

But that doesn’t mean it’s not possible. Watson is a highly athletic mauler without much coaching in his life. He doesn’t have most things that the typical second-round pick does. But he has size, and tremendous strength, both prerequisites for right tackle.

Watson earned the starting right tackle gig at Florida State with only one year of organized experience, and his upside is immense. But the NFL is a brutal place for a man with upside, size, but few years playing the game.

Feliciano is another “only way to go is up” type of player. He was taken in the fourth round of this year’s draft and wasn’t a known commodity nationally.

The potential is there — he’s got size, strength, and agility — but it’s hard to fathom Felciano as the future starter in Oakland over 10 seasons. That’s what the Raiders want, and that’s what they need, especially if there’s to be a running game turnaround.

Feliciano’s best shot at success is with a pulling scheme, which is where he excels. But the prospects aren’t terribly great. And that includes just getting the starting nod over J’Marcus Webb, Khalif Barnes, or another.

Jason Leskiw is SFBay’s Oakland Raiders beat writer and member of the Professional Football Writers of America. Follow @SFBay and @LeskiwSFBay on Twitter and at SFBay.ca for full coverage of the Oakland Raiders.