Thursday notes

NAPA — Raiders players and coaches should have been happier leaving the practice field on Thursday. They had just held their own against the Los Angeles Rams in the last of two joint practices and were looking forward to the preseason opener Saturday night.

But football doesn’t allow for too many happy moments. And so it was Thursday when one of the team’s sturdiest players, right guard Gabe Jackson, went down in practice with a left leg injury. He was carted off the field and into the locker room. Owner Mark Davis followed him in and then exited about 15 minutes later.

“We’re concerned, obviously, really concerned about him,” Raiders coach Jon Gruden said. “We’ll get more information here when we can be specific for you. I don’t want to speculate. …

“He just got rolled up a little bit unfortunately. Hope he’s OK.”

Jackson struggled to put weight on his leg before getting on the cart. He was later seen on crutches and wearing a knee brace.

Jackson, 28, played last season through a torn pectoral muscle and was really looking forward to playing alongside new 385-pound right tackle Trent Brown.

A third-round pick in 2014 out of Mississippi State, Jackson has missed only seven games in five seasons. He played two years at left guard before moving to the right side to make room for the since-departed Kelechi Osemele. Jackson signed a five-year contract extension in 2017 worth up to $55 million.

Denver Kirkland and Jordan Devey split first-team reps after Jackson left practice.

The Raiders will already be down a starting guard when the regular season starts, as Richie Incognito will be serving a two-game suspension for violating the league’s personal conduct policy. Free-agent signee Jonathan Cooper is expected to step in there.

Denzelle Good started three games at guard for the Raiders and seems to be making good progress from offseason back surgery. He has been working on the side with trainers at training camp.

“We’re missing Denzelle Good, obviously,” Gruden said. “So it’ll be a great opportunity for a guy like Denver Kirkland, who’s been here for a few years. We brought in Cooper to help at left guard. We’ll have to put our heads together, see where we are.”

No thaw yet
Antonio Brown has been gone from Napa for a week now, missing his 10th practice Thursday with “bad feet.” That’s still the official description, as the Raiders refuse to update Brown’s condition or even confirm national reports that Brown has frostbite on both feet because he wore the wrong shoes into a cryogenic chamber.

“He’s still gathering (information),” Gruden said. “I don’t have any information other than that.”

I then asked if Brown has frostbite.

“I’m not going to get into the exact nature of the feet,” Gruden said. “I’m just not.”

The Raiders originally thought Brown would be out no longer than a week. It’s been two.

General manager Mike Mayock didn’t offer up any update or new timetable, saying that he doesn’t discuss injuries this time of year.

Practice notes
• The offense was better the second day against the Rams, with Hunter Renfrow continuing to make every catch, including a touchdown in the corner, and J.J. Nelson caught a 50-yard strike from Derek Carr. Nelson has been moving around a lot with Antonio Brown and now Ryan Grant (back) out.

“He’s a guy that’s getting to run all the routes,” Gruden said. “I think he was more of a vertical stretch guy the last couple years but we’ve put him in the slot, we’ve put him everywhere with Antonio out and Ryan Grant didn’t play, so somebody has to step up. Every day, if you look at the film, Nelson is making big plays deep and Derek likes him and I think that’s something we’re going to continue to probe.”

• Rookie running back Josh Jacobs continued to look good against the Rams. I don’t expect Jacobs to get much run at all in the preseason, and Gruden said as much.

“We’re not going to go out and give Josh Jacobs 35 or 40 carries in August,” Gruden said. “But he carried the ball a lot in the last two days. I think you see vision. You see patience and you see burst. And what you haven’t seen is live full speed tackling and hopefully he gets a couple shots in August, but our fans will have to wait to see most of that when the Broncos come to town.”

The Raiders host the Broncos in the season opener.

• Left tackle Kolton Miller, meanwhile, gave up two sacks Thursday to Rams pass rusher Dante Fowler.