5 things learned in Sunday's preseason loss at San Francisco

Minnesota was handicapped with Adrian Peterson on the field for just two plays, hands off the ball.

The third preseason game is supposed to be the dress rehearsal for the regular season, the best example of what is to come in two weeks when the Minnesota Vikings open the season on Sept. 8 at Detroit.

As usual, the first-team offense and defense played longer on Sunday in a 34-14 loss at San Francisco, against one of the favorites to represent the NFC in the Super Bowl. Sunday's game wasn't as revealing as expected, in large part because Minnesota's MVP running back, Adrian Peterson, received only a courtesy appearance.

Peterson hadn't played in the preseason, and while he was on the field Sunday, what he did could hardly be called "playing." Peterson was on the field for only two plays and didn't carry the ball. Without their MVP, the Vikings offense was still less than full-strength.

What was learned from Minnesota's third preseason game? Not much really. Here's five things we think we learned:

1. Ponder is still an enigma

The Vikings are going into the season with Christian Ponder as the starting quarterback, and will stick with him as long as necessary to make a firm decision on his future as the starter. Ponder isn't making their choice a cinch though. His career was been filled with inconsistency and Sunday was another strange mix.

Ponder finished 17 of 23 passing for 116 yards, two touchdowns and one interception. The interception wasn't Ponder's fault as receiver Stephen Burton simply stopped on a slant pattern and the ball was tipped in the air by a defender for an easy interception. Yet, Ponder looked anything but comfortable. Ponder was dancing around the pocket, quickly getting off his spot. He fumbled on his third dropback of the game and was sacked once.

He was again operating without the MVP in the backfield, which will change the outlook and the defensive schemes. Ponder only completed four of his first seven passes as drives stalled. His best drive (8 of 10 passing for 49 yards) was the first drive of the second half and was against largely the second-string San Francisco defense. Ponder made some plays Sunday, but confidence can't be high going into the regular season, expecting the starters won't play in next week's fourth preseason game.

2. Felder keeping himself in punt return mix

Marcus Sherels didn't play Sunday as he was away from the team for a personal matter. Cornerback Bobby Felder got the chance to return the early punts from 49ers All-Pro punter Andy Lee and showed more good elusiveness and the ability to make the first defenders miss. Felder's first return went for 30 yards and he followed with a 10-yard return. He now has five returns the past two weeks for 102 yards (20.4-yard average). Last year's leading punt returner, Buffalo's Leodis McKelvin, averaged 18.7 yards per return.

Sherels ranked 20th in the NFL last year with a 9-yard average, which included a 77-yard touchdown. Felder has a chance to beat out Sherels for the top punt-return job and the fifth cornerback position. Minnesota could keep both players, but Felder has certainly put his name right there in consideration. The key will be proving he also is secure with the football and can be reliable on defense as well.

3. Worry about the cornerbacks?

One of the keys for Minnesota this season, aside from Ponder, will be the play of its young cornerbacks. Veteran leader Antoine Winfield was let go in the offseason and the Vikings drafted Xavier Rhodes in the first round. In doing so, second-year cornerback Josh Robinson was moved inside in the nickel defense and Chris Cook assumed the leadership role as the veteran among cornerbacks.

Robinson, who coaches said this week is much more comfortable inside than he was earlier, struggled mightily Sunday. He was beaten repeatedly by receivers, looking tentative off the line of scrimmage and he was also called for a pass interference penalty. Minnesota needs Robinson, who is still starting on the outside in the base defense, to be confident and able to cover the big-time receivers the team will face. Meanwhile, Cook, who's had his share of injuries in his career, left the game early because of a groin injury. If the Vikings could ill afford injuries at one position -- and coach Leslie Frazier told reporters after the game that defensive tackle Kevin Williams needs to have an MRI on an injured left knee -- it's cornerback.

4. Bishop might yet have some say at linebacker

A look at the leading tacklers for Minnesota on Sunday shows maybe a surprising name at the top. Desmond Bishop, signed before training camp, led the Vikings, unofficially, with nine tackles. One reason could be Bishop played a large portion of the game, getting time with the starters early and also played with the second-team defense in the second half.

Bishop, essentially, was getting his chance to show he can be the starting weakside linebacker. Marvin Mitchell has been starting all preseason and training camp at the spot. Bishop, finally healthy, worked with the first-team defense to see how he could handle working against quality competition. His return after missing all of last season with a torn hamstring and working with Minnesota's defense for the first time is still a work in progress, but his instincts are visible and he held up well Sunday, particularly against the run, slicing through blockers to make stops. With one preseason game left, and much of the first-team defense likely to sit it out, it will be interesting to see how the Vikings approach the Bishop-Mitchell decision.

5. Two receivers for one spot?

Another decision Minnesota will have to make is how many receivers to keep and who wins the final job. The Vikings had five receivers on the active roster last season during their playoff run and would likely be looking at five or six receivers this season. With four seeming locks in Greg Jennings, Jerome Simpson, Jarius Wright and Cordarrelle Patterson, a decision on the fifth would likely come down to Joe Webb and Stephen Burton.

Burton's been impressive during training camp and the preseason, but Frazier has warned about Burton needing to stay consistent. His mental error on the interception is just what Frazier has talked about. He simply stopped his route. He did catch three of his five targets Sunday for 31 yards to lead the team in each category. He had one kickoff return, in which he's being looked at as a possible backup returner, and it went for only 13 yards.

Webb, who is making the much-publicized move from quarterback, caught the only pass he was thrown. Webb went high against a defender to pull down a jump ball in the end zone for a 3-yard touchdown. Webb had a good week of practice and then pulled in the impressive touchdown Sunday from Ponder, who he once backed up.

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