ESPN's Adam Schefter first reported the two sides had struck a deal.
A 2013 first-round pick out of Syracuse, Pugh solidified himself as the Giants' most talented offensive lineman over the past five seasons while toggling between guard and tackle.
In 2017, Pugh played both positions but excelled most at left guard. However, he was plagued by injuries and appeared in just eight games before he was placed on season-ending injured reserve with a back issue.
Pugh hasn't appeared in a full 16 games since his rookie season.
However, the Cardinals were evidently willing to overlook Pugh's checkered past in the medical department and commit to him long-term because of his stout displays at left guard and ability to seamlessly switch between several positions.
"Justin is a guy who is a team player first," former Giants head coach Ben McAdoo said, according to ESPN.com's Jordan Raanan. "He goes out, he works hard, he brings his lunch pail, and he'll play any position that you ask him to play and won't bat an eye."
Quarterback Eli Manning espoused a similar opinion.
"Just a guy who is a warrior," he said, per Raanan. "Going to do whatever it takes and whatever the team asks him to do. I do appreciate it, being unselfish and doing what you have to do."
The Cardinals should be thrilled to add a player of Pugh's character, although they will hope for team-wide continuity along the offensive line in 2018 so their new signee can focus his attention on thriving at guard following a few hectic years with Big Blue.
If that winds up being the case, the Cardinals will be in a position to make strides in pass protection after allowing 52 sacks a season ago.