There is always an unknown that steps up. Derrick Henry steals the show against the Patriots, but Rashaan Evans plays like a madman on defense and comes up with key stops, and a guy from Harvard catches a touchdown. The Vikings likely lose if Anthony Harris doesn’t come out of nowhere to intercept an underthrown pass from Drew Brees. The playoffs are about your best players making plays, and an X-Factor contributing at a moment when you least expect it. Here is an X-Factor for the San Francisco 49ers on both sides of the ball.

McGlinchey will be tasked with stopping Danielle Hunter, one of the best pass rushers in the NFL. Hunter led the league in hurries, and was among the league leaders in sacks, and is second in combined pressures. He’s a stud. Hunter has seven sacks in the last five games. McGlinchey has turned the corner since he returned from injury. He struggled against Arizona in Week 11, but he’s been pitching shutouts pretty much since then. In the last six games, McGlinchey has allowed two sacks and zero quarterback hits. He’s performed like a top-ten pick, and the 49ers have needed him to.

I think this game will be a similar approach to the Saints game. Kyle Shanahan is going to come out throwing the ball all over the place, and with success. San Francisco has a great opportunity to take advantage of Minnesota’s depleted secondary, but it goes beyond the secondary. Linebacker Anthony Barr will likely be matched up against a Niners receiver. That’s a flaw in the Vikings scheme. Everyone has taken advantage of it over the years, and Shanahan will do the same. The 49ers offense has the advantage, but so did the Saints, until the Vikings edge rushers changed the game. If San Francisco Brees was sacked four times, and pressured 12 total times. Everson Griffen and Hunter are going to win, but it’s up to Joe Staley and McGlinchey to ensure that those wins don’t turn into sacks. If that happens, the 49ers will be in great shape.

I know Shanahan has said he doesn’t know who is starting at the other cornerback, but come on. You get fewer possessions in the playoffs, which means it’s even more important to limit the big play. I thought Ahkello Witherspoon was playing at an All-Pro level for a good bit of the season, but he fell off a cliff. It’s one thing to believe in your guys and stick by them; it’s another thing when said player costs you points.

Adam Thielen is a terror. He looked healthy, and when he is, Minnesota’s offense goes to another level. Moseley won’t be following Thielen, but the Vikings are going to come after Moseley, regardless. Against the Saints, Kirk Cousins threw the ball outside the numbers under ten yards to the defenses right (where Moseley would be) seven times compared to twice to the left. That’s not counting some deep post routes over the middle of the field, which happened three times. The Vikings do a nice job of getting Cousins out of the pocket on play-action bootlegs, so Moseley will have to be prepared for those deep comebacks as well. It’s every route, really. Stefon Diggs running timing out and slant routes are no easy task.

I think Moseley’s tackling is the big X-Factor. The Vikings are going to try and get Dalvin Cook to the edge. Most teams will have the receiver come block a defender in the box, which leaves the cornerback 1-on-1 on the outside. Moseley has been a willing tackler all season, and that needs to keep up. Aside from that, Minnesota is likely to run a heavy dose of quick screens to slow down the 49ers pass rush. Moseley needs to be aggressive and be able to get off blocks. It’s a huge game for a player that has played well all season. For what the Vikings do and do well, Moseley makes the most sense to start for the 49ers.