Brandon Scherff - Washington Redskins, 26
Brandon Scherff was selected 5th overall by the Washington Redskins in the 2015 draft. An offensive guard out of Iowa, Scherff has been one of the best parts of the Redskins since he joined the team. He has made three Pro Bowls, in 2016, 2017, and 2019 and has been one of the best run and pass members of the Redskins offensive line. Unfortunately for him and the team he ended the year with some injuries. Scherff should still get tons of interest in the open market and should see a massive contract, likely from the Redskins. The Redskins should and probably will do anything in order to keep their talented guard.
Anthony Castonzo - Indianapolis Colts, 32
Anthony Castonzo was drafted in 2011 out of Boston College in the first round by the Indianapolis Colts. He has played his whole career with the Colts, starting all 16 games for the team in both 2016 and 2017. He has been one of the consistent parts of the team and a leader for them on the offensive line. The Colts will likely try to convince their long time tackle to come back to the team and play for a couple more years. Given he spent his whole career with the Colts, they are the favorite to retain him.
Jack Conklin - Tennessee Titans, 26
Jack Conklin was picked 8th overall in the first round in 2016 by the Tennessee Titans after a spectacular career at Michigan State. He was a first team All Pro in his rookie season and was a Pro Bowl alternate in 2017 but his career has gone down significantly since then. Despite having started most of the games for the Titans since he joined the team, the Titans declined his 5th year option which will make him a free agent. This makes it likely that Conklin will be on a different team in 2020 although a good year by the offence might have the Titans wanting to keep much of the team together. As one of the younger players available Conklin is likely in for a significant contract.
Joe Thuney - New England Patriots, 27
Joe Thuney is an offensive guard that the Patriots drafted in the third round in 2016. Since he was drafted he won the starting left guard position and has played nearly every game for the New England Patriots since then, winning two Super Bowl Championships. Thuney should get a good amount of interest in the open market but the patriots will likely want to bring back one of their offensive line members. That being said, expect uncertainty in New England until the future of Tom Brady is sorted out. Either way, Joe Thuney should be a well paid starter next season.
D.J. Humphries - Arizona Cardinals, 26
D.J. Humphries has been one of the more well regarded lineman his whole life, winning an award in high school as the top lineman, going to the University of Florida, and being selected in the first round of the 2015 draft by the Arizona Cardinals. He has struggled with injuries throughout his time with the Cardinals and has had trouble staying on the field and with consistent play. The Cardinals did, however, pick up his 5th year option which indicates their interest in keeping him a part of the team. As one of the youngest left tackles available, Humphries will likely get a lot of interest from NFL teams.