49ers joint practices with Vikings revealed these key weaknesses

The 49ers wrapped up two days of joint practices with the Vikings ahead of preseason Week 2, and the scrimmages revealed some notable issues.

If you were to ask San Francisco 49ers head coach Kyle Shanahan, joint practices and scrimmages are much more valuable than any preseason game his team could play.

However, if you were to ask wide receiver Brandon Aiyuk what he thought of the two-day practice session with the Minnesota Vikings, he would tell you they were “a waste of time.”

The reality is likely somewhere in the middle. Preseason games only mean so much, and half-speed scrimmages against another opponent aren’t going to generate any sweeping conclusions either.

However, while there were plenty of reasons to be excited about the Niners’ efforts, a number of significant issues also popped up.

Particularly these three weaknesses that could end up plaguing San Francisco over the course of the upcoming 2022 season.

49ers weakness No. 1: Running back depth is already an issue

Presumed starting running back Elijah Mitchell has been nursing a hamstring injury and didn’t take the field for the 49ers’ exhibition win over the Green Bay Packers, and he likely won’t face off against the Vikings this Saturday.

That would be fine, as it would mean more chances for depth rushers like Trey Sermon, Jeff Wilson Jr., JaMycal Hasty and Jordan Mason to see more field time. However, on day two of practices, Sermon exited with what appeared to be a foot injury.

Two tailbacks are potentially down out of five vying for critical roles this season.

Granted, the Niners have three weeks to get both Mitchell and Sermon back to 100 percent and fully healthy, but the attrition already starting to hit long before the regular season commences is a pretty big concern to monitor.

49ers weakness No. 2: Cornerback depth chart is top-heavy

Earlier this offseason, San Francisco was looking at a fully revamped cornerback room with the hope it had turned from a weakness in 2021 into a strength in 2022, thanks largely to the free-agent pickup of Charvarius Ward and the Round 5 NFL Draft selection of Samuel Womack.

Womack has been great from offseason workouts through scrimmages with the Vikings, yes. But Ward and fellow starting corner Emmanuel Moseley have also been banged up.

In the wake of the 49ers parting ways with veteran Darqueze Dennard and being without fellow veteran Dontae Johnson (ribs), the defense has been forced to rely upon reserves buried well down on the depth chart, such as Ambry Thomas, Deommodore Lenoir and Ka’Dar Hollman.

This isn’t necessarily bad in a practice setting, since Ward, Moseley and now Womack all have defined roles heading towards the regular season, while Thomas, Lenoir and Hollman are all vying for one or two depth spots on the 53-man roster.

However, the recent shade of injuries has revealed how even just one or two injuries can turn a strength into a weakness, and it isn’t as if these backups performed well against Minnesota in practice.

49ers weakness No. 3: Right side of O-line still a question mark

Like the Niners’ cornerback room, the offensive line is appearing to be pretty top-heavy, and that’s been exposed with right tackle Mike McGlinchey still working his way back from quad surgery last year.

While the left side of the O-line generally held its own against the Vikings, fill-in tackles Justin Skule and Colton McKivitz were less than desirable on the side opposite left tackle Trent Williams, and Sports Illustrated’s Grant Cohn summed things up with regards to day one’s showing:

"The 49ers offensive line gave up four sacks during 11 on 11s. After practice, Kyle Shanahan said the 49ers’ pass protection performed about how he expected it would, which means he expected it to struggle. So did I. The 49ers offensive line isn’t good enough."

Read More: 5 Niners who need a bounce-back preseason game vs. Vikings

Quarterback Trey Lance has shown some maturation in navigating pressure and learning how to hit his hot-route receiver in these situations, yet the second-year pro was still under duress for both days, and Thursday’s practices with backups in front of him didn’t exactly prompt any additional confidence.

Granted, neither Skule nor McKivitz are expected to hold any significant role this season, provided they both make the 53-man roster, yet it’s another key example of why someone like McGlinchey is so vital to stay healthy.

Yet he, Lance and the bulk of San Francisco’s starters probably won’t be suiting up when the 49ers square off against the Vikings for Week 2 of preseason action on Saturday, Aug. 20 at 7 p.m. ET.