However, there are other ways they can get the playoff spot:
1. Carolina/New Orleans tie PLUS Arizona loss
2. Carolina/New Orleans tie PLUS San Francisco loss
3. Arizona loss PLUS San Francisco loss
It's pretty simple: if the Panthers beat the Saints this Sunday, they're in the driver's seat to win the NFC South. They don't clinch the division because both teams still have one more divisional game left (Panthers/Falcons, Saints/Bucs), but at the very least they will be assured a spot in the NFC playoffs.
But, if the Saints win on Sunday all is not lost. The Panthers will still have a shot to make the playoffs depending on how the 49ers and Cardinals fare this Sunday, so for good measure let's all root for the Seahawks and (hold your noses) Falcons to win this weekend.