Herm Edwards says Atlanta will beat New Orleans in a "must-win" game at home. (0:50)

New Orleans Saints running back Mark Ingram, who hasn't participated in full-team drills for two days because of a toe injury, is expected to play in Thursday night's NFC South showdown in Atlanta, a source told ESPN's Adam Schefter.

In addition, rookie cornerback Marshon Lattimore, who was listed as questionable due to an ankle injury, is also expected to play, a source told Schefter.

The Falcons also got some good news, as cornerback Desmond Trufant will play Thursday night after returning from a concussion.

Ingram has 922 rushing yards, 255 receiving yards and nine touchdowns. Along with rookie running back Alvin Kamara (1,220 total yards), the Saints' backfield duo is on pace to become the first pair of running back teammates each with more than 1,500 yards from scrimmage in NFL history.

Kamara, who has 11 touchdowns, leads the NFL with 7.0 yards per carry.

The Saints (9-3) have a chance to widen their lead in the NFC South on Thursday night at Atlanta. The Carolina Panthers (8-4) are in second place, but the Saints swept their regular-season meetings against Carolina. The Falcons (7-5) are two games back -- but this will be the first of two meetings between the Saints and Falcons over the next three weeks.

New Orleans definitely will be without starting left guard Andrus Peat, who was ruled out Wednesday with a groin injury.

Peat will be missed. But the Saints have a very experienced backup in veteran Senio Kelemete. And ideally they will get left tackle Terron Armstead back from thigh and shoulder injuries that sidelined him last week. Peat replaced Armstead at left tackle when he was hurt, with Kelemete filling in for Peat.

The Saints are also hoping to get rookie safety Marcus Williams (groin) back from injury. He is listed as questionable, along with Armstead and defensive end Trey Hendrickson (knee).

ESPN's Mike Triplett contributed to this report.