By Lewis Gould

The Eagles are a big 8-point underdog in this Sunday’s showdown with the Saints, and that’s probably because New Orleans waxed the Birds 48-7 in November.

And if they have any hope to win and go on to the NFC championship game they have to master this match-up:

Saints wide receiver Michael Thomas vs. Eagles’ backup cornerbacks

The Eagles contained Thomas in their Week 11 blowout loss to the Saints. Thomas was held to four catches, 92 yards and a touchdown.

In actuality, it took them double-teaming Thomas almost the entire game to only hold him to those figures.

In that 48-7 defeat, Eagles D-boss Jim Schwartz dialed up some of the quirkiest coverages you’ll ever see — not only doubling Thomas, but also double-covering Alvin Kamara out of the backfield on the same play. The result was Saints wide receiver Tre’Quan Smith going off for 157 yards on 10 catches.

Therein lies the problem with facing Drew Brees:

He only needs a step of separation to burn your defense. In PFF’s advanced quarterback charting, we found that Brees completed 79.1 percent of his attempts when his receivers had only a step of separation — the highest figure in the league by 5.3 percentage points. The Eagles may have been able to get away with their ragtag secondary in the elements against Mitchell Trubisky, but that seems doubtful in the Superdome against Brees. We’ll likely find out very early on if the Eagles trust their corners to go one-on-one with Thomas, and how they hold up will go a long way toward deciding the game.