Mack was embroiled in a lengthy lockout that lasted all preseason until the Raiders worked out a trade with the Bears. Oakland received a 2019 and 2020 first-round pick, a 2020 third-round pick, and a 2019 sixth-round pick in exchange for the 2016 Defensive Player of the Year, a 2020 second-rounder, and a conditional fifth-round pick that same year.
In an interview with ESPN, Raiders head coach Jon Gruden placed the blame squarely on the shoulders of Mack for his departure. "Obviously, Khalil Mack didn’t want to play here. That’s what’s being missed here," Gruden said. "He was under contract, Lisa, you know, 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."
"Obviously, Khalil Mack didn't want to be here."— NFL on ESPN (@ESPNNFL) September 10, 2018
– Jon Gruden pic.twitter.com/t1NQzF5bVo
Gruden can try to accuse Mack of not wanting to be in Oakland, but Mack wanted to be paid what he thought he was worth as he entered his fifth-year option worth $13.8 million. If there's anyone who could understand that mentality of wanting to get paid, it would be Gruden, who returned to coaching in the NFL after signing a reported 10-year, $100 million contract with the Raiders in January.
Khalil Mack and the Bears just reached agreeement on a record-setting 6-year, $141 million extension ($23.5M per year avg) that includes $90M guaranteed and $60M at signing, source tells ESPN.— Adam Schefter (@AdamSchefter) September 1, 2018
Mack is the new highest-paid defensive player in NFL history.
Instead of accepting his current deal with free agency looming next offseason, Mack wanted to move past his contract deal and become the highest-paid defensive end in the league.