The Vikings needed to upgrade the defense from 2011, but from what was on display against the 49ers in San Francisco on Friday night, that hasn’t happened. The defense struggled all game long. They were missing three key starters in DT Kevin Williams, DE Jared Allen and CB Antoine Winfield, but it likely wouldn't have made a difference in the17-6 loss.

The 49ers ran over the Vikings defense, putting up 17 points and 198 yards on the ground in the first half. Late in the second half, with the 49ers trapped near their goal line with third and long, the defense was gashed up the middle for a first down and coach Leslie Frazier was seen shaking his head on the sidelines.

"There are some things we've got to work on, our run defense especially,” Frazier said. “We will address those issues at camp next week."

The defense looked particularly bad when it was fooled by an option fake; Niners backup QB Colin Kaepernick ran virtually untouched for a 78-yard score. That gave the 49ers a 14-3 lead, and they never looked back. Eventually, the 49ers knelt on the ball and ran out the clock with two minutes left in the game and the ball on the Vikings 2-yard line. They employed the mercy rule in the first preseason game.

Ponder pleases: QB Christian Ponder may have answered some questions about his readiness with his one quarter of work against the Niners. He was 4 for 9 for 80 yards, but he had at least two drops and wisely threw away two more passes. Both throwaways were followed by Vikings field goals. More than that, Ponder looked poised in the pocket, and he only pulled the ball down early and took off running once. It was a small sample size but good results.

Smith impresses: Rookie FS Harrison Smith didn't get in the game until the second quarter, but he momentarily shined on a defense that often didn’t. Brought up tight on the line to help with run coverage, he made good reads and was quick to the ball, and he made one solo tackle. He wasn’t tested in deep-pass coverage, as the 49ers ran the ball often, and he was pulled relatively quickly for someone who is a rookie backup. That may be an indication that his backup status could change sometime before the regular season.

Walsh kicks well: Vikings fans collectively exhaled with the performance of K Blair Walsh. The rookie Walsh came into camp without competition, but he performed well when faced with his first experience of NFL pressure. Walsh hit field goals of 39 and 26 yards and put his three kickoffs into the endzone -- one for a touchback and two for short returns.

“It’s exciting; it’s fun to play at this level,” Walsh said. “Obviously, I wish the (game) result was different, but I am glad with the work we got in today. We’ve got to continue to get better. We have two attempts under our belt, so far. I’ve got to keep getting more attempts and get more comfortable.”

Webb struggles: If QB Joe Webb was in a position battle with starter Christian Ponder, the gap between them just got wider as Webb struggled mightily and looked a little lost at times. Webb was given five series to get something done, and the only thing he did was escape the constant rush without injury. In his two quarters of work, he produced no points and only three first downs, going 4 for 11 for 20 yards.

Good news on Guion: The bad news of NT Letroy Guion’s injury turned into better news after the game. He has a strained PCL (posterior cruciate ligament) in his knee and is expect to be out for only 1-2 weeks. The quick return of the starting run stopper is good news for a defense that had trouble stopping the run.

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