Jefferson was placed on injured reserve on Wednesday after injuring his knee in practice last week.
Jefferson's injury is serious enough to require surgery, but his absence shouldn't have much of an impact as he appeared in just three games and recorded one tackle this season. Defensive end Malliciah Goodman was signed to the 53-man roster to fill the vacant spot.
This will be the second consecutive game missed for Jefferson due to his thumb injury. Frank Clark should see an increased workload while providing depth at defensive end while Jefferson is sidelined.
Jefferson previously required surgery to repair a thumb injury and had been slotted for a Week 7 return. Now practicing without restraint, it appears said prediction will prove accurate, barring a setback in practice this week.
Jefferson (thumb) will not play against the Falcons on Sunday, ESPN's Liz Mathews reports.
Jefferson underwent surgery to heal an injured hand two weeks ago and was given a 2-3 week timeline to return. Thus, he figures to have a good chance of playing in Week 7.