What to know when the Vikings play the San Francisco 49ers at noon today at U.S. Bank Stadium:

Vikings vs. 49ers

When >> Noon today

Where >> U.S. Bank Stadium

TV >> WCCO Ch. 4

Radio >> KFAN 100.3 FM

Line >> 49ers -5

Over/Under >> 46.5

Keys for the Vikings

• Can they keep quarterback Sam Darnold upright? That will be the biggest question. It was clear watching Darnold play against the New York Giants in last week’s season opener that he’s more than capable of finding open receivers if he has time to operate. That might be easier said than done against the 49ers. Obviously it helps that Darnold has the luxury of throwing to star receiver Justin Jefferson, who has proven throughout his career he can change the game at a moment’s notice.

• The pressure the Vikings were able to generate against 49ers quarterback Brock Purdy last season was a big reason they came out on top. A consistent pass rush got Purdy off his game and he looked rather uncomfortable as the Vikings pulled the upset. If defensive coordinator Brian Flores can follow a similar script this time around, the Vikings might be able to do it again.

Keys for the 49ers

• Never mind that 49ers backup running back Jordan Mason performed so well in the season opener. The presence or absence of top running back Christian McCaffrey will play a big role in this game. If he’s available, the Vikings will absolutely have their hands full. If he’s not available, the 49ers will need another solid performance from Mason, which is far from a guarantee.

• It will be interesting to see how 49ers edge rusher Nick Bosa fares against star Vikings left tackle Christian Darrisaw throughout the game. Both players are among the best in the NFL at their respective positions so the matchup should provide some fireworks.

— Dane Mizutani