© Isaiah J. Downing-USA TODAY Sports

SANTA CLARA – The 49ers are undefeated in the preseason, Jimmy Garoppolo has one more interception than he has yards (zero) and there’s plenty to figure out before the team heads down to the nation’s capitol of humidity, Tampa Bay, Florida, for the first game of the season against the Buccaneers. It’s a weird time in which debates continue to reign over whether the preseason matters at all.

The preseason does matter, but not at all in the sense that a bad six-throw performance (two of which were swatted at the line) from Garoppolo signals doom. It’s about evaluating the talent in the back half of the roster and cleaning up mistakes like the ones Garoppolo made. Speaking of which…

What happened on that Garoppolo pick?

Here’s the play below, in which Jimmy Garoppolo, on his second play back after a nearly 11-month injury absence from a real football game, threw an interception. It looks all sorts of weird. Bradley Chubb gets pressure on Garoppolo with no issue whatsoever, going virtually untouched on a miscommunication between Joe Staley (who thought he had help inside) and Laken Tomlinson.

https://twitter.com/Supreme_gifs/status/1163616402277748736?s=20

The play looked especially odd because Marquise Goodwin ran a short comeback route, discernibly as a decoy, and stopped early enough that Broncos corner Isaac Yadom was perfectly positioned to make the interception before Matt Breida could get deep into his go route. It was perfectly poor timing and decision making.

Initially, head coach Kyle Shanahan said he believed Garoppolo was hit on the play, but after watching film, found fault in both the offensive line’s miscommunication, and Garoppolo’s play. Again, it’s been 11 months since Garoppolo faced live competition, and in Shanahan’s analysis of the play, it’s clear there’s rust in Garoppolo’s game. He had two options: throw the ball away or take the sack. Instead, Garoppolo forced a throw and it was picked off.

“We had a miscommunication in protection, so some guys came in there, the defensive end, Chubb got in there early, earlier than I expected,” Shanahan said Tuesday. “I thought Jimmy got hit as he was throwing it. He didn’t. He got rid of it too early to avoid the hit and the route hadn’t developed yet so it didn’t go far enough down the field, so we need to do better job in protection there by getting everyone on the same page and we need to do better at throwing that ball away, or, if you can’t, you have to take that sack.”

Concern for the backup offensive line

When Shon Coleman went down as the 49ers’ reliable swing tackle, it bumped Vanderbilt rookie Justin Skule up in the pecking order. When Josh Garnett went out at the start of camp with surgery on his finger, and Mike Person has dealt with small knocks, the same thing happened to Najee Toran.

Both were repeat penalty offenders on Monday. Both Skule and Toran had a pair of holds (Skule had another in Game 1), and Toran, slotted in at center with Nick Mullens at quarterback, had a fumble on the snap. The offensive line committed eight penalties in the first game against the Dallas Cowboys and the problem persisted in the second game.

Yes, it’s the preseason, and worrying about the performance of the starting offensive line after the miscommunication on the Garoppolo interception is overreacting. But the preseason is for finding out who can fill out the rest of the roster, and while that picture is becoming clear in most other position groups, there’s not much, if any clarity, with the backup offensive line.

Shanahan said that he’s bothered by the penalties.

“It concerns me,” Shanahan said. “You need to be able to block and you need to be able to do it without holding and we’ve gotten way too many of those in these last two weeks, so it’s something we definitely have to improve.”

As for the depth, well, there’s two more games to figure that out, but someone will need to stand out.

“Depth on the O-line is something every team is trying to work at,” Shanahan said. “We need some guys to step up. We’ve lost the two guys who were competing at guard with Person and Garnett and that’s opened up some opportunities for these guys and that’s why they’ve been in there a ton in these two games. They have had some really good plays that show that they can play in this league, but just like you guys have noticed, they’ve had too many penalties and they’ve had some bad plays. The good thing about this stuff is we do have two more games and it’s something that we haven’t seen yet to where we can figure it out. We need more game tape and hopefully one of these guys can step it up.”

No word on the backup QB

Nick Mullens has looked the better backup quarterback, but you’re not going to hear that coming from Shanahan, at least not until a decision is officially made, which most likely won’t come until cut down day on August 31. Shanahan said he feels confident in both Mullens and C.J. Beathard, who he believes have improved, and has yet to decide who will start with the second team against the Kansas City Chiefs on August 24.

“I believe in both of those guys and I believe they can play. We’ll see who we decide to go in with the second group this week; haven’t decided that yet,” Shanahan said. “And whoever we do, we plan on the next guy getting a lot in Week 4. I’ll never make a decision before the fourth preseason game comes, but usually the backups are the guys who play really the entire game, so there’s a lot more playing time for both of them to get here. I feel very good with both the guys. We’ve had both the guys here in a lot of game situations, but it’s been a fun battle to watch and I think both of them are playing better than they have the last two years.”

After jokingly asking, ‘Do you want me to tell you?’ who the backup quarterback would be, followed by a duet of reporters responding, “Yes,” Shanahan reaffirmed his support for both quarterbacks.

“I know we have two backup quarterbacks who are both capable of starting and I would be happy with either one as our backup,” Shanahan said. “One of those guys is going to win that job. We will make that decision. I do not see myself making that decision until I absolutely have to and that probably won’t be until the final 53, but if we make it before then and there’s no advantage in hiding it, I promise you I’ll let you guys know.”

Injury updates

• Weston Richburg is stealing on PUP, but the 49ers are targeting his return to practice before the team plays the Los Angeles Chargers in its final preseason game in the hope that he can be back for Week 1.
• Mike Person will be evaluated for his foot sprain when the team gets back to Santa Clara, and is being targeted to return to practice on Thursday
• Jerick McKinnon, who had a plasma-rich platelet (PRP) injection for soreness in his knee, is not going to be involved in team drills this week, but may get individual work starting on Thursday.
• Dee Ford, who also had a PRP shot for his knee tendinitis, was initially expected to be back for this week’s series of practices, but will likely be pushed to next week. Said Shanahan: “That was the goal. We got back from traveling. Right now, if you had to ask me I don’t think we would throw him in tomorrow just traveling like this and the fact that we’re going to not be full speed. We’ll look at it again the next day. With this short week happening, I know that was the goal for it or we thought there was a possibility. I still think there is, but I think we are going to be leaning a little bit more towards next week.”
• Shawn Poindexter is feared to have torn his ACL, but nothing has been confirmed as the team waits for X-ray results. Chris Thompson, who was signed then cut to make room for Jeremiah Valoaga after a host of defensive line injuries before the first preseason game, will be signed once the results are official for Poindexter

Final notes

• Shanahan was a fan of the booming tackle by rookie punter Mitch Wishnowsky, though he wasn’t surprised by it. Said Shanahan: “I was not shocked at all. That’s what rugby players do. I don’t know if we want to make a living out of that, but it’s good for the other 10 guys to see. If they’re not on it, he might get down there and take their stats away. I was very impressed with it. It was a perfect form leverage side tackle that was very impressive.”

Hey @49ers what are you feeding your special teams unit? @mitchwish#SFvsDEN pic.twitter.com/2qRdYICdaX

— NFL (@NFL) August 20, 2019

• Jalen Hurd only took eight snaps on Monday because he had back stiffness. As far as the receiver competition goes, Shanahan is still waiting for someone to help make his decision for him. He was happy with Deebo Samuel’s 45-yard end around, but said he expects him, with his speed to make plays like that.

• While the backup offensive line struggled to block without drawing penalties, Kaden Smith excelled, and was recognized by Shanahan when asked about the pair of key blocks he had in sealing the back edge for Samuel’s run, and for the Raheem Mostert touchdown run. Said Shanahan: “I thought he’s done a good job. He’s gotten better here with these opportunities with the tight ends being down. He had a good week of practice and he did real well in the game, those two runs in particular, and he helped us out in the pass game also.”