Oakland Raiders defensive end Khalil Mack continues to hold out in hopes of landing a long-term contract, and it sounds like he's prepared to go great lengths to try and get what he wants.

According to Charles Robinson of Yahoo Sports, Mack "is now likely" to sit out regular season games, and a source informed him that the two parties haven't had "meaningful talks" in months.

Mack is in the final year of his rookie contract, and he's certainly worthy of an extension in the $90-100 million neighborhood. If he sits out regular season games, Mack will lose millions in fines, but the Raiders seemingly aren't willing to negotiate right now.

RUMOR: RAIDERS AND KHLAIL MACK NOWHERE CLOSE IN CONTRACT TALKS

Credit: Cary Edmondson-USA TODAY Sports

The Raiders gave Jon Gruden a 10-year, $100 million contract to return as their head coach, and perhaps he doesn't value Mack enough to get him on the field as soon as possible. Gruden is known for being more hands-on and tough with his players, and he took a shot at Mack, saying the defense wasn't good in 2017, even with the Pro Bowler.

Mack is arguably the NFL's best defensive player, and game-changers like him simply don't grow on trees. The Raiders have to decide soon if they're going to pay Mack, because it seems like he's not going to end this holdout.

There are a handful of teams that would certainly give up multiple draft choices to acquire Mack. He's good for double-digit sacks and is one of the most freakish athletes in the world. If the Raiders don't want to pay Mack, they better trade the Pro Bowler and get something, rather than see him walk in free agency.

The Mack situation is an ugly one right now, and there doesn't appear to be an end to this in sight. Unless he has a change of heart and opts to end the hold out, it seems like the Raiders will take the field in 2018 without their franchise player.

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