The Oakland Raiders are coming off a disappointing 2017 season that saw them take a significant back a year after snapping their decade-plus playoff berth drought. This has shifted the franchise toward making several notable changes to help them get back on the right track as one of the top teams in the league.

Much of these alterations are expected to come on the defensive side of the ball,as that was where the Raiders had most of their issues this past season. Not everyone is leaving, of course.

According to Ian Rapoport of The NFL Network, Oakland has secured veteran defensive tackle Justin Ellis under a three-year deal worth more than $15 million.

Ellis was on track to hit the open market after completing his four-year, $2.7 rookie million deal. Since being selected in the fourth round of the 2013 NFL Draft, he has developed into a highly dependable player for the Raiders along the defensive line. He has proven to be an effective factor against the run and is coming off a career-high 48 tackles while playing in all 16 regular season games for the third time in his first four seasons.

The next move for the Raiders may be to get defensive end Denico Autry, under a new deal as he is also set to hit the free agent market after completing his one-year, $1.8 million deal. However, this could become quite tricky with the Raiders only possessing $19.1 million in salary cap space this offseason.

Jon Gruden, Raiders
Marcio Jose Sanchez/The Associated Press

Oakland is believed to have some significant interest in signing cornerback Trumaine Johnson, who is expected to become a free agent after the Los Angeles Rams agreed to a trade to land Aqib Talib from the Denver Broncos.

Johnson is expected to draw a high price tag given that he will be one of the top players at his position on the open market. Despite the limited amount of salary cap space, the Raiders appear to have a game plan in place to improve their defensive unit.