Of course, Jon Gruden is an optimist. NFL head coaches can see the bright side of even dark situations and believe their teams can adapt, improvise and overcome to prove wrong all doubters and naysayers.

So it’s not a surprise that Gruden believes guard Gabe Jackson will play this season, and sooner than some people think.

“Yeah, he’s doing good,” Gruden told Levi Damien of SB Nation. “I see him walking around, which is a great sign. Rehab is going well. I don’t know when he’s going to be ready. I don’t even know if we are going to put him on IR (injured reserve), honestly, but his progress has been good. We’ll see where we are after the Seahawk game and make that final determination.”

The durable Jackson suffered a torn knee ligament (medial collateral) early in training camp and team physicians indicated he’d be out of action about two months. That means Jackson, who starts at right guard, would miss about the first month of the regular season.

In his place, Jordan Devey is expected to start, meaning the Raiders will be without their two top guards to start the season. Richie Incognito is suspended for the first two games, so Jonathan Cooper will take his place. That leaves the Raiders in a shaky spot in the middle of their offensive line, which they hoped to improve this offseason with the signing of right tackle Trent Brown and Incognito.

As Damien noted, with roster cut-down day Aug. 31, the Raiders have plenty of decisions to make after Thursday’s exhibition finale in Seattle.

Wrote Damien: “If they think Jackson will be able to return on time to play week five, they may keep him on the active roster. If not, they must consider putting him on IR with designation to return. That would have him return to practice as early as six weeks into the season and play at eight weeks.”

The loss of Jackson has been perhaps the most serious injury suffered by the Raiders this summer. Flanked by center Rodney Hudson and Brown, the right side of the O-line looked formidable heading into training camp. Without Jackson and with Devey, there’s much more danger of a lack of pass protection for Derek Carr and fewer holes for rookie running back Josh Jacobs.

Devey – who ordinarily would be a backup at both center and guard – knows he must perform with Jackson on the sidelines and support his O-line mates, QB and running backs.

“It’s really the only position on the field where if you mess up, somebody could get hurt,” Devey told Paul Gutierrez of ESPN. “So there is that protective instinct that you have and then you have to be a little bit off in the brain to do what we do. It’s physical – every play we’re banging heads against somebody and so you have to be kind of wired differently.”