It appears that Oakland Raiders star defensive end Khalil Mack is prepared to hold out for a big contract.

Mack is not expected to attend the Raiders' mandatory minicamp this week, sources told NFL Network's Ian Rapoport. A three-time Pro Bowler, Mack is entering the final season of his rookie contract, which according to sports salary information site Spotrac, will pay the defensive end more than $13 million in 2018.

Per Spotrac, Mack's 2018 salary is set to make him the NFL's fourth highest-paid defensive end, but Mack is likely seeking deal with long-term security

Since being selected fifth overall in the 2014 draft by the Raiders, Mack has been nothing short of stellar in his brief career. He's posted 40.5 sacks in his four season and has recording double digits numbers in the category the past three seasons.