Matt Cassel will start at QB for the Vikings on Sunday, and the official reason being given is that Christian Ponder has not passed his concussion test after being knocked from the game against the Bears at halftime.

The honest truth is that Cassel is a better quarterback than Ponder and certainly gives the Vikings a better chance to win.

With that in mind, we thought it might be fun to look back at the season and imagine how it might have played out differently if Cassel had been the starter all season. Keep in mind, of course, this is all purely speculative and hypothetical:

Week 1: 34-24 loss at Detroit. Ponder started and threw three interceptions, including a game-turner with the Vikings leading 14-6 late in the first half and driving for more points. Detroit got the ball and scored to make it 14-13 at the break and went on for the victory. Win probability if Cassel starts: Tossup.

Week 2: 31-30 loss at Chicago: The Vikings were tied 14-14 in the second quarter because of a kickoff return and fumble return for TDs. Then Ponder threw a pick-six and it was 21-14 Bears. Ponder responded and played decently the rest of the way, but he and the offense couldn't cash in a late drive for a TD. They settled for a field goal, the Bears scored in the final minute and there you have it. Win probability if Cassel starts: 60 percent.

Week 3: 31-27 loss to Cleveland: Ponder had just 228 yards passing and an interception on 42 attempts, but he did have a pair of rushing touchdowns that had the Vikings in position to win, leading 27-24 late. The defense couldn't hold, and another late close loss was at hand. Win probability if Cassel starts: 60 percent.

Week 4: Cassel started in London against the Steelers. The Vikings won.

Week 6, after bye: Cassel started vs. Carolina. The Vikings lost. Carolina has won 8 consecutive games starting with that one.

Week 7: 23-7 loss at New York. Josh Freeman started and was awful. The Vikings actually led 7-3 in the first quarter thanks to a Marcus Sherels punt return for a TD. That was their only score of the game against the Giants, who were almost as inept. Win probability if Cassel starts: Tossup.

Week 8: 44-31 loss to Packers. Ponder plays OK, but the Packers shred the Vikings' defense. Win probability if Cassel starts: Low.

Week 9: 27-23 loss to Dallas. Playing one of the worst pass defenses in the league, Ponder is decent. His fumble in the end zone is recovered by the Cowboys for a 20-10 lead, but he helps lead two TD drives to reclaim the lead at 23-20. But a critical three-and-out with a chance to ice the game haunts Ponder and the Vikings, as Dallas rallies late to win. Win probability if Cassel starts: 60 percent.

Week 10: 34-27 Vikings win. Ponder plays quite well but is knocked out of the game setting up the go-ahead TD at 28-27. Cassel relieves and leads two field goal drives, and the defense holds on for the win. Win probability if Cassel starts: Tossup.

Week 11: 41-20 Seattle. Vikings are clobbered. Ponder has an awful second half, but this game was not determined by the QB. Win probability if Cassel starts: Low.

Week 12: 26-26 tie vs. Green Bay. Ponder plays decently in helping the Vikings build a 23-7 lead, but the offense stalls in the fourth quarter as the Packers rally to tie. In overtime, the Packers kick a field goal but the Vikings come back and get one, too -- largely thanks to their ground game -- and the game winds up tied. Win probability if Cassel starts: 60 percent.

Week 13: 23-20 win over the Bears: Ponder is knocked out at halftime with a concussion after going just 3 of 8 for 40 yards. Cassel relieves, leads a late rally to force overtime, then the Vikings kick the game-winning field goal in OT. Cassel finishes with 243 yards, one TD and an INT -- on a ball that should have been caught for a touchdown. Win probability if Cassel starts: 80 percent.

So what we have is this: Five games the Vikings lost and one tie in which the difference between Ponder or Freeman and Cassel, in our mind, might have made the difference in a victory. One game in which Ponder started (and won) that we're not sure Cassel would have won.

Our best guess is the Vikings very well could be .500 if Cassel had started all season. In this year's NFC North, that would mean they were in the thick of the race.

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