Raiders need boost — how soon might Carr give it?

The Raiders have a problem. They need a jump-start. A quick start. They need to get their offense rolling. Yet it seems they will have to do that with a backup quarterback and a stalled running game.

I say “it seems” because there was an interesting development at the Raiders’ practice Thursday afternoon. Injured quarterback Derek Carr, who was not at practice Wednesday, was on the field, at least during the first 30 minutes that media members were allowed to observe. Carr participated in all the stretching and warm-ups, then took snaps and threw passes to receivers. He and backup EJ Manuel alternated snaps.

It would be highly unlikely — and bordering on medical malpractice — to play a quarterback who was diagnosed Monday with a fracture in his back (a transverse process fracture). So we’ll assume that Carr is simply feeling good and wants to keep his arm and habits fresh. But, his participation could be an indication that Carr might be back more quickly than a worst-case, mid-November scenario.

Meanwhile, with or without Carr, the Raiders’ offense is a puzzle.

In the offseason, Oakland dismissed offensive coordinator Bill Musgrave and elevated Todd Downing, who had been the quarterbacks coach. Carr came into camp healthy. The team added running back Marshawn Lynch. Amari Cooper and Michael Crabtree were a dangerous receiving tandem. The offensive line was touted as one of the best in the league.

Yet, the results in the past two weeks have been disappointing. Granted, the two losses came against good opponents, but the Raiders’ offense just hasn’t been able to get on track.

“We’re close,” tackle Donald Penn said. “We’ve got to start doing better early. We haven’t started as fast as we need to, so that we can sustain drives.”

The running game has been particularly anemic the past two games, with a combined total of 56 yards.

Some of that might be playing from behind, or not being able to run the ball. Some of that might be the inability to convert third downs (2-for-23 in the past two games), which means the offense hasn’t gotten into a rhythm.

“I think it’s varied,” Downing said of the running-game problems. “It’s some situational stuff, a little bit of misfortune, a little bit of missed execution and I can certainly call it better. Of the pie that is the run game, there’s plenty of pie to dole around to each group.”

Another piece of the pie is the focus on Lynch. One of the great running backs in NFL history, Lynch is naturally a featured back. But because of his age, he didn’t play much in training camp. And he’s in a new scheme. Lynch on his hometown team remains a work in progress.

“He’s still learning,” Penn said. “It’s a totally different scheme from what he ran in Seattle.”

On the unhappy flight home from Denver on Sunday, Lynch, Penn and Rodney Hudson went over game video together to see what each man was reading on various plays. Despite the paltry rushing yards against the Broncos (24), Penn was encouraged by what he saw.

“We’re not far away,” he said. “We’ve got to have all 11 on their job, all at the same time. It’s so close, but close don’t get you nowhere in the NFL.”

The Raiders’ offensive numbers are down dramatically from the first four games of last season. They are recording an average of almost six fewer first downs, averaging 105 fewer net yards per game and almost 40 fewer rushing yards per game.

Last year, the Raiders were 3-1. One of those victories was over Baltimore, the team they will face Sunday. The Ravens have had their own struggles, and their 21st-ranked defense might not scare anyone. Except that the Ravens’ defense is usually intimidating.

“They’re in the same spot as us,” Penn said. “They’re clawing. We’re clawing. They have big guys. They’re hard to move. They’re pretty straightforward.”

The Raiders’ offense should get Crabtree back; the receiver who suffered a bruised chest against Washington and missed the Denver game has participated in practice.

“It may have taken some things off the plate from his route-tree standpoint, but it wasn’t a factor in us not playing well offensively,” Downing said.

(Yes, he said “route tree” to me and — please note, Cam Newton — I did not faint or collapse in confusion.)

Downing will have a challenge this week: jump-starting the offense while also keeping it simple enough for Manuel to succeed.

“If you stick to bread-and-butter stuff and go with concepts the quarterback is familiar with, it’s a little bit easier,” Downing said.

But right now, nothing is coming easily.