The Eagles answered one of their huge offseason question marks Thursday by signing defensive tackle Tim Jernigan to a four-year contract worth $26 million guaranteed, ESPN's Adam Schefter reported Thursday.

The deal adds four years to Jernigan's current contract, which was due to expire after this season. So he's now signed through 2021.

Jernigan has played only nine games in an Eagles uniform but has established himself as a formidable piece of one of the NFL's most dominating defensive lines. The numbers - 20 tackles, eight tackles for loss, 1½ sacks, five hurries - don't really come close to describing how disruptive Jernigan has been. His performance alongside Fletcher Cox has been widely credited for Cox's return to his All-Pro form.

Jernigan, originally the Ravens' 2014 second-round pick out of Florida State, is earning $1,017,284 million this year in the final year of his rookie contract. The deal the Eagles gave him kicks in next year.

On that defensive line, which has helped carry the Eagles to an NFL-best 8-1 record and a seven-game winning streak at the bye week, Cox is signed through 2022, Jernigan, Barnett and Chris Long through 2021, Vinny Curry through 2020, Brandon Graham through 2018 and Beau Allen through this season.

The Eagles had about $6.3 million available under their 2017 adjusted salary cap figure of just under $175 million. Jernigan's exact cap figures will be available when the specific year-by-year breakdown of his deal becomes available.