No. 2, Colt McCoy, QB
Aside from Colin Kaepernick, none of the 49ers quarterbacks should feel secure. But McCoy is in the most danger. He completed just six passes in the first two games and has two interceptions. He'll be the second quarterback to enter the game, but three others are gunning for the job. The 49ers recently re-worked McCoy's deal so that he'll make the league minimum this year. With a solid outing, that would make him more likely to stay. But it also makes him easier to trade.
No. 18, Seneca Wallace, QB
Wallace was signed Thursday and after just two practices with his new team, he'll be given set list of plays to run in today's game. A solid outing can't hurt the Rando Cordova product. But Wallace's spot on the team has more to do with how McCoy and Scott Tolzien (No. 3) play against the Vikings. Another quarterback, B.J. Daniels (No. 5), also will play. Daniels is second only to Kaepernick in physical ability among the Qbs. Read more about him here.
No. 84, Jon Baldwin, WR
The 49ers want to get Baldwin up to speed as quickly as possible, so he should see a significant number of snaps. With one catch, he will have the same number of preseason receptions as his predecessor, A.J. Jenkins.
No. 11, Quinton Patton, WR
Baldwin isn't the only 49ers' receiver making his preseason debut. Patton, a fourth-round draft pick, also will be on the field after recovering from a broken index finger. Patton had been running routes in practice but was unable to catch the passes that went his way. That is, his injury didn't force him entirely out of practice, and it will be interesting to see how much this eager rookie plays today. Patton has a strong chance of being one of the five or six receivers to make the 53-man squad.
No. 6, Austin Collie, WR
The 49ers will keep either five or six wide receivers on the 53-man roster. If it's five, Collie may be out. He's entered late in the last two games with the reserves. An earlier entrance might signify that Collie has risen in the ranks since the last game.
No. 32, Kendall Hunter, RB
Hunter reported that he's back to normal after recovering from an Achilles' tear suffered on Nov. 25. This will be his first game action since the injury. A little rust is to be expected, but if Hunter is indeed his old self he can be expected to take over the No. 2 running back role behind Frank Gore this year. The extent of Hunter's recovery also is interesting in that the team's top receiver, Michael Crabtree, also is attempting to come back from an Achilles' tear this year.
No. 35, Eric Reid, S
The 49ers' first-round draft pick likely will make his first start against the Vikings. He's been good in practice and smart in games, and he's on track to being on the field when Aaron Rodgers and the Packers come to town Sept. 8. Only a big mistake or two can throw him off track now.
No. 24, Nnamdi Asomugha, CB
He's close to securing the role of No. 3 cornerback. He's coming off a good game against the Chiefs and could win it with another strong performance. The third cornerback - Chris Culliver's job the last two years - typically doesn't start but plays 70 percent of the defensive snaps.
No. 57, Michael Wilhoite, ILB
He has a firm hold on a roster spot. But this game is important because of who likely will line up opposite him - Adrian Peterson in his first game of the preseason. Wilhoite said he'd love to test himself against the Pro Bowl running back.
No. 86, Brian Jennings, LS
Get ready for what is likely your first-ever longsnapper-scouting assignment. For the last 13 seasons, the position has been unremarkable because the man playing it, Brian Jennings, has been machine-like in his snapping ability. This year, Jim Harbaugh said the competition between Jennings and rookie Kevin McDermott (No. 47) is "very, very even." Is it? Jennings had a perfect snap when the 49ers had to punt from their own goal line in Kansas City, which led to a booming punt by Colton Schmidt. It's hard to think that a team with Super Bowl aspirations would trust the long-snapping duties to an undrafted rookie.
- Matt Barrows