There are upsets every week, but it's quite hard to pick them out of the weeds.
We eliminate the guesswork and tell you the biggest upsets of Week 10.
Lions Over Vikings
The Lions have been a big disappointment this season, but they have a good chance to redeem themselves this week against the Vikings.
Matthew Stafford is on an upward swing. In the last three games, Stafford has completion percentages of 60.9, 69.4 and 66.7, respectively.
He's also really good against the Vikings. In his last three games against Minnesota, he's averaged over 300 yards passing, five touchdowns and no picks.
The Vikings have lost two straight and three out of their last four. It's going be tough for them to stop Stafford. Look for the Lions to pull off the upset.
Saints over Falcons
The Falcons are 8-0, and odds are against them going undefeated. So the question becomes who they lose to.
It's possible that they will lose to the Saints. The Falcons have not faced an offense like the Saints, who boast the second-best passing offense in the league.
While the Falcons have a decent defense, they haven't faced the best teams. They gave up 21 points to Denver in Week 2, but that was when Peyton Manning was still finding his way.
So when the Saints come in, it's going to be a bit of a culture shock for the Falcons defense. They don't have top cornerback Brent Grimes, and there's no one on the defense to match up with Jimmy Graham.
The Saints defense isn't good, but if it comes down to a shootout, the Saints have more offensive firepower to edge the Falcons out and gain the upset.
Raiders over Ravens
The Raiders are clearly not the same defense now that Ray Lewis and Ladarius Webb are out. They have the 22nd-ranked pass defense in the league and the 28th-ranked run defense.
The Raiders throw the ball a lot, over 40 times a game. They have the sixth-best pass offense and average 281.3 yards per game.
This is bad news for the Ravens. Last week, Carson Palmer threw for 414 yards and four touchdowns against the Bucs.
The high-octane offense of the Raiders against the woeful pass defense of the Ravens could mean a long day for the Ravens, as they lose in an upset.