The Falcons went on to confirm the deal after the start of the league year.
Rapoport added that the first two years of the deal are guaranteed, with guarantees in the third year as well. He also added that Mack was able to secure those because of interest from teams such as the Cleveland Browns and San Diego Chargers.
Peter King of Sports Illustrated added Mack's deal will average $9.5 million per year, noting Mack could have received more by returning to the Browns, but Falcons offensive coordinator Kyle Shanahan played a factor in his deciding to join a new team.
Mack, 30, is considered one of the top interior linemen in the NFL and has been voted to three Pro Bowls since the Cleveland Browns drafted him with the 21st overall pick in 2009. He voided his contract with the Browns this offseason—the team would have paid him $8 million a year over the final three years of that deal—and hit free agency looking to secure one last lucrative contract.
Mack's addition should dramatically improve the Atlanta offensive line, namely inside.
One concern will be whether Mack is back to full strength after breaking his fibula in 2014.
Khaled Elsayed of Pro Football Focus noted: "As he worked his way back from injury, he didn’t look like the guy he was before getting hurt. A very average year, with him not generating a lot of movement in the run game and allowing too much pressure. He’s played a lot better and not made the Pro Bowl."
The Falcons are certainly banking on a return to elite form for Mack.
His loss is a major blow for the Browns, meanwhile, as the team was trying to retain him. With Mack gone, promising young guard Cameron Erving—who was the No. 19 overall pick in the 2015 draft—will likely slide over to center.
It could be a rough offseason for Cleveland's offensive line, as right tackle Mitchell Schwartz is also a free agent. Losing both Mack and Schwartz would be a huge blow for Cleveland's line and for its offense in general.
For Atlanta, meanwhile, Mack addresses one of the team's biggest needs coming into the offseason—the interior of the offensive line. Last year, the team shuffled among Mike Person, James Stone and Gino Gradkowski at center.
This year, the position has been solidified with Mack.
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