Raiders' Gruden: 'Obviously, Khalil Mack didn't want to play here'

Jon Gruden appears to have some lingering bitterness toward Khalil Mack.

In an interview with ESPN's Lisa Salters that will air in full on Monday Night Football, the Oakland Raiders head coach implied that his decision to trade the star pass-rusher was about more than just finances.

"Obviously, Khalil Mack didn't want to play here," Gruden said. "That's what's being missed here. He was under contract. He never showed up for an OTA, he never showed up for training camp, and it was obvious he wasn't going to show up for the season. So don't forget that."

Mack, who was entering the fifth-year-option season of his contract prior to being traded to the Chicago Bears, held out from all team activities in search of a new deal.

Related: Carr on Mack trade: 'It isn't what anybody wanted'

Gruden said last week the Raiders weren't close to the contract offer Chicago gave the All-Pro defender, and insisted he's only focused on the players currently on his roster.

"We have to get ready to play," Gruden said. "And I want players that want to be here, that want to help us put this thing back in high gear."

Mack had an electrifying debut with the Bears on Sunday night, accumulating a sack, a fumble recovery, and an interception return for a touchdown.