Jake Long has signed a four-year contract with the St Louis Rams worth $34m (£22.5m).
The offensive tackle, who was the top pick in the 2008 draft, had been a free agent after coming to the end of his contract with the Miami Dolphins.
The 27-year-old told the Pst-Dispach: "It was a tough decision. I came in for a visit and coach [Jeff] Fisher and Kevin Demoff and Les Snead were amazing.
"I just fell in love with their vision and the entire organization. And all the great things they had to say about Mr [Stan] Kroenke and the way they go about football."
Long missed the final four games of the 2012 season after tearing his triceps.