NFL Week 13 upset picks: Chargers have chance to do some damage in Pittsburgh

One of the major keys for the Los Angeles Chargers' hopes for an upset in Pittsburgh is how well Austin Ekeler picks up where Melvin Gordon left off as the primary running back. Michael Goulding/Zuma Press/Icon Sportswire

Did you enjoy last week's spate of double-digit lines? Good for you, because we've got four more of them to contend with in Week 13. All four double-digit favorites covered last week, and we're not going near those double-digit lines for this week's Upset Watch and Cover Watch. Our Upset Watch game is a much closer battle, between two teams hoping to dethrone the New England Patriots atop the AFC, while our Cover Watch game has two teams trying to find consistency.

Upset watch: Los Angeles Chargers at Pittsburgh Steelers (-3.5)

Football Outsiders' playoff odds give each of these teams more than an 89 percent chance of making it to this year's postseason, but there's still a lot of movement left when it comes to playoff seeding. The Chargers still have a shot at the AFC West title and even the No. 1 seed if they can keep pace with Kansas City. Pittsburgh needs to win to get the highest seed possible.

Based on both Football Outsiders DVOA and ESPN's FPI, the Chargers are the better of these two teams. Both methods have the Chargers ranked fourth in the league. DVOA has Pittsburgh seventh, while FPI has the Steelers fifth. DVOA has the Chargers ahead of the Steelers on both offense and defense, although the gap on defense is a smaller one.

When Pittsburgh is on offense, the key