John

Estes

Estes was expected to be a swing-backup lineman in Jacksonville this year, but it sounds like his knee injury is significant enough to threaten his roster spot. The Jaguars are reeling with offensive line maladies, so much so that they recently had to convert rookie defensive tackle Drew Nowak to guard.

Estes hasn’t appeared in a game since 2011 with the Jags. The Jacksonville coaching staff was once high on him, but injuries have limited Estes to two career games. Consider him a roster long shot, even on the Cardinals.

They waived G Christian Johnson in a corresponding move. 27-year-old Estes is a journeyman who’ll likely serve as a practice body before final cuts.

Estes’ only two career appearances came in 2011. Neither Brackett nor Rowe has ever appeared in an NFL game.

Estes, undrafted in 2010, did not suffer a serious injury, but the Jags couldn’t hold a roster spot entering Week 1. Starting C Brad Meester turns soon, so Estes could have a chance to replace him eventually. Estes was a heralded pass blocker in college, operating in OC Nick Rolovich’s run-and-shoot.

Estes had been dealing with an MCL injury. The Jags signed undrafted rookie center Bradley Vierling to take his roster spot.