He played the previous nine seasons for the New Orleans Saints, which selected him in the first round of the 2015 NFL draft.

As a high school senior, he was considered the best college football recruit by Sporting News.

[1] Peat attended Corona del Sol High School in Tempe, Arizona, where he was a letterman in football, basketball and track.

[10] At the 2015 NFL Combine, commentator Mike Mayock appraised Peat's 40-yard dash, "He's got dancing feet with that lower body, it's unbelievable.

On September 20, 2015, he received his first career start at left guard in a loss to the Tampa Bay Buccaneers.

During a Week 6 matchup against the Atlanta Falcons, Peat suffered a leg injury that would force him out of action for the next 3 games.

[18] In the wild card round of the playoffs, Peat was carted off with an air cast on his left leg.

He was diagnosed with a broken fibula and a high ankle sprain and was placed on injured reserve on January 10, 2018.