Saints left tackle Terron Armstead is expected to miss three to four weeks with a pectoral injury, according to Ian Rapoport of NFL.com (on Twitter). Armstead suffered the injury in Sunday’s one-sided win over the Bengals. 
The Saints turned to veteran Jermon Bushrod after Armstead’s exit, so it stands to reason that he will start in Armstead’s absence. The Saints also have Michael Ola and tackle/guard Chaz Green to support Bushrod and Ryan Ramczyk, so they don’t necessarily have to add a tackle this week.
With an 8-1 record, the Saints are fighting more for playoff positioning than a postseason berth. They have a comfortable, though not insurmountable, lead over the 6-3 Panthers for the NFC South title and they are second only to the 9-1 Rams in the NFC. Clearly, they did not miss a beat after Armstead’s exit on Sunday, so this is unlikely to unravel the Saints’ passing offense in the coming weeks.
Armstead, 27, ranks as the league’s No. 1 overall tackle this year, according to Pro Football Focus.