Minnesota quarterback Christian Ponder has completed a league-leading 75.8 percent of his passes through two games. (US Presswire)

49ers at Vikings -- Week 3

Where: Mall of America Field--Metrodome, Minneapolis, Minn. (turf, indoors)

When: Sunday, 1 p.m. ET (FOX)

Spread: 49ers by 7

Records: Vikings (Overall: 1-1, NFC North: 0-0); 49ers (Overall: 2-0, NFC West: 0-0)

Past results: Two most recent meetings -- Sept.. 27, 2009: Vikings 27, 49ers 24; Dec. 9, 2007: Vikings 27, 49ers 7. Series record: 49ers lead the series 22-21-1.

What matters: The Vikings need to do everything they haven’t done to this point in the season -- start fast, finish drives with touchdowns and play tough defense for all four quarters. They will need to find a receiver to stretch the 49ers defense down field to keep them honest and out of the box so RB Adrian Peterson has room to run. Theyneed to find someone else to throw to beside WR Percy Harvin (T-2 in receptions in the NFL) because if they don’t, an excellent 49ers defense will double him and take away QB Christian Ponder’s favorite target. The Vikings' defensive line will have to do more than just chase 49ers quarterback Alex Smith -- it must sack the quarterback, which it has done once in two games. The secondary can’t continue to give up big plays.

Who matters: Ponder needs to show he's ready to play with the other quarterbacks in the NFC North Division. If the 49ers’ vaunted defense is vulnerable anywhere it is through the air as it ranks 19th against the pass. But one must consider the 49ers first two games were against reigning MVP Aaron Rodgers and Lions QB Matthew Stafford, who threw for more than 5,000 yards last season. The Niners’ defense is tougher against the run (ranked sixth, giving up only 63.5 ypg), so Ponder will need to play the whole game like the finished the previous two, when he put his team in position for a game-tying field goal in the waning seconds in Week 1 and throwing two late touchdown passes to the Colts with 31 second left last week. If he is unsure of where he is going with the ball or late in his progressions, the 49ers defense will make him pay for it.

Key matchups: TE Vernon Davis vs. the Vikings. Davis will be a difficult matchup. Davis is a speedy tight end who will be difficult for the Vikings linebackers to cover over the middle. With three touchdowns in two games, Davis is tied for the NFL lead in scoring, and will look to exploit the Vikings' pass defense. It gets even tougher for Minnesota if LB Erin Henderson, who is tied for third in the NFL in tackles, can’t go because a concussion.

Injuries of note: Henderson left the Colts game with what was thought to be an elbow injury, but was pronounced fine after the game. On Wednesday, he did not practice because of a concussion. Meantime, DE Brian Robison injured his left elbow and was wearing a large brace on it at practice. He was not limited at Wednesday’s practice.

Inside stuff: You won’t hear much about this since the Vikings are 1-1 and the offense has gone through periods in each game where it has sputtered, but Ponder leads the NFL with 75.8% completion percentage. It’s a small sample size with just two games, but completion percentage is something that Ponder wanted to improve this season. Now, if he can maintain that percentage and complete a few more shots downfield, you may start to hear more about it.

Connections: Mike Singletary, special assistant to head coach/linebackers for the Vikings, was head coach of the 49ers two seasons ago. In addition, 49ers WR Randy Moss spent seven and a quarter seasons in Minnesota. His return to the Metrodome should be very interesting on Sunday. Moss was asked if he expects to hear boos at the game.

Stat you should know: Last year WR Percy Harvin wasn’t getting used enough, so went the weekly complaint. It’s hard to say that so far this season when you consider that Harvin had a career-high 12 receptions last week and has caught 18 of the 21 passes thrown his way in 2012. Harvin’s 18 receptions are the most by a Viking through the first 2 games of a season, passing by legends Cris Carter (1997) and Randy Moss (2002), who each recorded 17.

Bulletin board quote: "One thing about praises and boos is obviously you're doing something right. I think I just hang my hat on that," Moss said. "You hear the applause, of course you do, and you hear the boos, but I think the boos just being negative puts more pressure on you to go out and hush that noise up. So I look forward to hearing both and, like I said, I'm a 49er now and hopefully we can go into the Metrodome and come out of there 3-0."

Record watch: If K Blair Walsh can knock one through from 50 or more yards out, he will set a Vikings team record for most consecutive games with a field goal of at least 50 yards. He tied former Viking K Fuad Reveiz last week at two consecutive games...Vikings WR Michael Jenkins will hope to extend his streak of 54 consecutive games with a reception in which he’s played. Last season, Jenkins missed the final five games with a knee injury.

Looking ahead: The Vikings travel to Detroit to take on the Lions in the two teams’ first NFC North Division meeting of the season. The San Francisco 49ers head to New York to battle the Jets and their two-headed quarterback monster of Mark Sanchez and Tim Tebow.

Prediction: 49ers 30, Vikings 17

For more Vikings news and notes, follow Joe Oberle on Twitter @CBSVikings.