Sources: Eagles' Jernigan has back surgery

Eagles starting defensive tackle Tim Jernigan underwent surgery on a herniated disc in his back last week and is expected to be out four months, league sources told ESPN.

SportsRadio 94WIP first reported Jernigan's surgery.

The Eagles are hopeful to have Jernigan back for the team's Thursday night regular-season opener against the Atlanta Falcons, sources said.Dr. Robert Watkins performed the surgery, according to a source.

The injury easily could have ended Jernigan's time in Philadelphia, with the Eagles releasing him and declining to pay him, since he suffered the injury during an offseason workout in March. Instead, the Eagles reworked his contract. They will still pay him the $3 million that's guaranteed for this season, under the original terms of the four-year, $48 million extension he signed in November. But they will no longer be liable for the $11 million guaranteed that was due in 2019 as part of the deal.

Under the terms of the new contract, the final three years are now option years, with Jernigan scheduled to make $11 million in 2019, $12 million in 2020 and $12 million in 2021, as was the case under the previous terms. However, none of the salary in those final three years is guaranteed.