The Dallas Cowboys are expected to sign free-agent offensive tackle Cameron Fleming, a league source told ESPN's Field Yates.
This means the New England Patriots are poised to lose both of their starting offensive tackles from Super Bowl LII, as starting left tackle Nate Solder signed with the New York Giants.
The Cowboys also restructured the contract of 11-time Pro Bowl tight end Jason Witten, creating roughly $3.5 million in salary-cap space, sources told ESPN's Todd Archer.
Witten's is the second contract the Cowboys have reworked in the past week, along with the deal of Pro Bowl center Travis Frederick that created nearly $7 million in cap room.
The 320-pound Fleming, who entered the NFL as a 2014 fourth-round draft pick of the Patriots, rotated between third and fourth on the depth chart at the start of the regular season. He ultimately became the top replacement for injured right tackle Marcus Cannon by the end of the season.
Fleming played in 12 regular-season games (six starts) and started two of the Patriots' three playoff games. His presence as a powerful blocker on the edge, which he had shown in Stanford's pro-style offense, is one of his primary assets.
Coach Bill Belichick complimented Fleming several times over the past four years. Belichick called him one of the most respected players on the team in 2016 and most recently said in December, "Cam's been a solid player for us for four years, and he's always been ready to step in whenever we've called on him at both tackle spots and sometimes at guard and jumbo tight end and things like that."
Fleming, 25, majored in aeronautics and astronautics at Stanford. At 6-foot-6, he said he is one inch too tall to be an astronaut, so he put all of his effort into professional football.
ESPN's Mike Reiss contributed to this report.