CBS college basketball analyst Bill Raftery has a saying when a player -- oftentimes a star -- comes through in a clutch situation: "ONIONS!"

Will Vikings running back Adrian Peterson prove to have "ONIONS" in Sunday's playoff game? If he doesn't, the Vikings will be one-and-done for a second consecutive season and 13th time in team history.

"I want to be the best there is and ever was," Peterson told NFL Fanhouse when asked what he wants to achieve. "I don't just want to be the best running back that has ever played football, I want to be the best player to have ever played football."

The player Peterson is most frequently compared with -- Walter Payton -- was just ordinary in nine career playoff games, so postseason success is not mandatory to make the Hall of Fame. But to be considered the "best there is and ever was" it is.

Peterson hasn't played like the best or second-best running back on the planet this year. Outside of abusing Cleveland's Eric Wright in the first game and showing flashes of greatness versus Baltimore, Peterson hasn't had a Hall of Fame-esque season. His numbers, especially his 43 catches, are good, but don't blow you away. In 2008, he went over 100-yards in a franchise-record 10 games. This year he has just three 100-yard games. 23 percent of the Vikings' runs have not gained at least one yard, which is 2nd-worst in the NFL.

Footballoutsiders.com on the Vikings' running game: The 2009 Minnesota Vikings do not have a great running game. They don't even have a good running game. What they have is a running back who is great when he's not having fumbling problems, and a seriously overrated offensive line that has steadily declined over the course of the year.

Peterson has put the ball on the ground seven times this year and since entering the league in 2007, leads all non-quarterbacks in fumbles (20).

A superstar running back can ever so slightly makeup for a subpar O-line. Before the regular season finale against an unmotivated Giants team, Peterson had gone six straight games averaging less than four yards per rush. Four of which came against bottom-half rush defenses (Chicago x2, Arizona, and Carolina).

His missed block on the first play of last year's playoff game set the tone for Philadelphia's blitz package the rest of the day. In that loss, he ran for 83 yards on 20 carries.

The best way to negate Dallas' top-notch pressure is to establish a run game. Yes, it's true that they haven't allowed a 100-yard rusher all season, but they also haven't seen a running back capable of doing what Peterson can.

Four of Peterson's six best games have come against the 3-4 look, which Dallas features. His top career game -- 296 yards vs. San Diego in 2007 -- was accomplished when seeing the 3-4. Current Cowboys tackle Igor Olshansky was a starter on that Chargers defense.

I get the sense after talking with well-spoken right guard Anthony Herrera in the locker room on Friday that the Vikings truly believe that they can have success in the run game.

Former Vikings head coach Jerry Burns had a saying before entering a big game: "We've got to make sure that our big knockers knock." Whether Peterson "knocks" on Sunday will go a long way in determining if he is a big-time player who delivers in big-time games or if he is just a big-time player.