All eyes will be on Adrian Peterson versus 49ers

The Minnesota Vikings are going primetime in more ways than one for their third preseason game on Sunday at San Francisco.

The third preseason game always holds more meaning, and features more time for the starters. Minnesota will be on Sunday Night Football and will get a look at one of the favorites in the NFC for the Super Bowl.

Here are five things to watch as the Vikings travel to face the 49ers:

1. A certain running back in the backfield

There’s a little matter of Adrian Peterson playing in his first preseason game. Remember him? The MVP running back has practiced throughout the offseason and training camp, but hasn’t played in the preseason. Not surprisingly, Minnesota’s offense has looked a little disjointed without its best player. Peterson’s arrival in the backfield should change the outlook, from the Vikings’ point-of-view as well as the way defenses attack.

Minnesota’s offense still begins with Peterson as option 1. Coach Leslie Frazier has said the offensive and defensive starters will play into the second half on Sunday — to have the experience of going in and making halftime adjustments, and then taking them to the field — but it’s unlikely Peterson will play as long as the rest of the starters. The coaches want to see Peterson work with the offense and get time as a complete unit. Peterson wants to get some work and said he’d be happy playing the first half, but the guess is Peterson would probably play the first few series and then sit down in hopes of avoiding injury.

2. Backups with the starters

The Vikings aren’t shaking up the depth chart, per se. The usual starters will start Sunday for Minnesota, which should include injured linebacker Erin Henderson and left guard Charlie Johnson, who has missed the past two practices while dealing with a personal matter. Instead, coaches will take time in Sunday’s game to see how some of the team’s backups work with the first-teamers, specifically on defense.

The two biggest names to watch and see how they work with the first-team are linebacker Desmond Bishop and receiver Cordarrelle Patterson. The Vikings want to see how Bishop does against San Francisco’s best players as they judge the linebacking crew. When Bishop signed following the offseason program, many believed he’d be a starter. But Marvin Mitchell has held on to the starting spot at weakside linebacker. Sunday is Bishop’s chance to prove he should be the starter when Minnesota opens the season on Sept. 8.

Patterson is still behind Jerome Simpson at receiver. However, Jarius Wright will miss the game as he comes back from a concussion. The Vikings are holding him out even though he’s passed the concussion testing. Wright is set as the team’s third receiver. Patterson should take his place Sunday and get the chance to work with the first-team offense and starting quarterback Christian Ponder in three-receiver sets.

3. A read-option preview

The 49ers might not have started the latest offensive trend in football, but they certainly perfected it on the way to the Super Bowl last season. The read-option offense with quarterback Colin Kaepernick at the helm confused defenses late last season after San Francisco totally revamped its offense under Kaepernick from the power-running, timing-passing offense of Alex Smith. The fact Minnesota faces the 49ers in the third preseason game where the starters will play more is significant.

Sunday will test the Vikings’ defense both against the run with San Francisco back Frank Gore and Kaepernick, the pass with Kaepernick and the read-option offense, which Minnesota will see variations of four times this season. Minnesota has studied the scheme and the defense will get its crack at the newest fad and will be testing the team’s linebackers and young secondary, specifically. The Vikings couldn’t have asked for a better dress rehearsal for their season than getting the 49ers in the third preseason game.

4. Time to Ponder

Ponder’s preseason has only opened up the criticism on the third-year quarterback more as he’s struggled in his two brief appearances. Minnesota is counting on Ponder this year and he is as important to the team’s success as the MVP Peterson. San Francisco also features one of the league’s top defenses, but it’s one in which Ponder succeeded against last season. In a big early season win last year, Ponder was 21 of 35 for 198 passing, 33 yards rushing and three total touchdowns with no turnovers.

Ponder and the offense should benefit from having Peterson in the backfield, the first true indication of the complete offense during the preseason. Ponder still needs to work on his timing with his receivers such as Greg Jennings. The offensive line also could use a better showing than last week where it struggled snapping the ball and dealing with the Buffalo Bills blitzes. A little added confidence or comfort from a good showing Sunday would help Ponder and the offense going into the regular season and maybe back a little of the heat off the group.

5. Last chance

Minnesota gets the chance to bring much of its 90-man roster to San Francisco, but the traveling party will be much shorter in the following games. On Tuesday, the Vikings will have to make their first cuts and get down to the 75-man limit for the fourth preseason game. On Aug. 31, Minnesota will make its final cuts to get to the 53-man active roster.

This could be the last NFL game for some on the Vikings’ roster. Minnesota has to give its starting units extended time in the final test-run for the season, but also must make decisions on the players on the roster bubble. Frazier said he will play several players that the team needs to decide on after the starters leave the game in the third quarter. For some, it’s their last chance to stand out for the coaches and general manager Rick Spielman. Six days after Sunday’s game, Minnesota’s roster will have been trimmed from 90 to 53, leaving a lot of players looking for work.

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