PFF says 49ers rookie lineman crashed back to earth in Week 2 loss to Vikings

Dominick Puni was excellent in his NFL debut, but the rookie struggled mightily in the 49ers' Week 2 loss to the Vikings.

So much can change in the NFL on a week-to-week basis, and that football facet rings true for one of the San Francisco 49ers' biggest high-profile rookies.

Starting right guard Dominick Puni was excellent in his regular-season debut, helping the Niners dominate the New York Jets in prime time and opening up all kinds of lanes for running back Jordan Mason, who churned out a whopping 147 yards and a touchdown in the process.

Understandably, this led many to believe San Francisco found an absolute gem out of Kansas in Round 3.

However, Puni's efforts in the 49ers' Week 2 road loss at the Minnesota Vikings left a lot to be desired.

And it's fair to remind everyone that Puni is, well... still a rookie.

Pro Football Focus slams Dominick Puni in Week 2

Granted, Puni doesn't bear the entirety of responsibility for the Niners' 23-17 defeat at US Bank Stadium. Not even close.

Additionally, Mason still managed to gain 100 yards rushing again.

However, on a day when San Francisco's offensive line wasn't quite up to par, Puni was graded by Pro Football Focus as the biggest liability from this unit.

Overall, Puni received a 49.8 overall game grade, the lowest of all the 49ers' starting offensive linemen and even lower than embattled right tackle Colton McKivitz (66.3). And while the former wasn't credited with allowing a sack, he was hit with giving up three quarterback pressures.

As for his run-blocking efforts, Puni didn't exactly receive praise from KNBR 680's Dieter Kurtenbach:

Now, this isn't a reason to go all "panic mode" regarding the Niners' first-year pro. Puni is going to take some lumps in year one, and it's also pretty apparent Minnesota employs a potent front seven on defense under coordinator Brian Flores, whose schemes frustrated the entire O-line and quarterback Brock Purdy, too.

If Puni chalks Week 2 up to being a vital learning experience, he'll be better for it.

However, if repeated struggles become the norm, fans can understandably begin to worry.

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