Five days before the 2018 season began, the Raiders sent Khalil Mack to the Bears in exchange for draft picks in one of the biggest NFL trades in recent memory. The Raiders went on to win four games in Jon Gruden's return to the sideline and committed fully to the rebuild by also shipping off Amari Cooper before the trade deadline. The Bears went on to win 12 games and the NFC North to snap their playoff drought.

There's no doubt the Mack acquisition elevated the Bears from a fringe playoff contender to a legitimate Super Bowl hopeful considering the Bears' defense, with Mack leading the way, emerged as the league's best. There's also no doubt the Mack trade devastated an already bad Raiders defense considering the Raiders finished the year with a league-low 13 sacks. 

Now, Raiders offensive tackle Donald Penn is here to tell us just how much the Mack trade impacted the Raiders from a locker room perspective.

"No matter what nobody says, we tried to overcome it. But when you trade your best player away in the beginning of the year, it takes a toll on guys," Penn told NFL Network's Lindsey Rhodes on Wednesday.  "Whether they say it or not. We fought through it. We tried to stay together. It was a tough season.

"Khalil Mack is one of my good friends. I'm happy he did what he did. But I knew kind of when I saw Aaron Donald sign that deal I kind of knew in the back of my head that we weren't going to be able to sign Khalil cause all the money he was going to ask for. I knew what Gruden was coming from cause I might know different cause I been in the league for so long. I know it's a business."

That should sound familiar. Immediately after the trade, Raiders quarterback Derek Carr (after he tweeted "No way") admitted that it wasn't "what anybody wanted."

Well, besides the Bears and Mack. The Bears immediately handed Mack the massive contract he desired. Mack, in turn, helped turn the Bears into contenders with 12.5 sacks in 14 games. In other words, he finished half a sack shy of the Raiders' team total in two fewer games. 

Still, Penn reiterated that he understands why Gruden traded Mack and Cooper, pointing to the Raiders' collection of draft picks. They have three first-round picks in this year's draft, giving them a chance to successfully rebuild a broken team.

"And this year we have all these draft picks. We have all this cap room," Penn said. "If we would've signed Khalil we might not have that. I understand kind of why he traded [Amari] Cooper away, too, cause now we have another draft pick and we have more cap room cause Cooper would've had to get signed this offseason. And, it's not my decision. My decision, I would've kept Coop. I love Coop. That's my boy.

"But at the end of the day I've been in the league for 13 years. I know [it's] a business. That's a business decision that's made. I'm behind Gruden. Guys are behind Gruden. We're ready to get to work and turn this thing around."

To "turn this thing around," Gruden and new general manager Mike Mayock will need to hit on most of their draft picks, because they're missing more than just an elite pass rusher and receiver. They've got holes everywhere -- including, probably, at quarterback where Carr has emerged as a competent, but not elite option. The Raiders' first pick will come at No. 4, but they'll be forced to wait until the back end of the first round to make their final two selections after Mack and Cooper helped propel the Bears and Cowboys to the playoffs, which lowered the draft picks the Raiders acquired from those two teams. 

In my latest (and first) mock draft, I've got the Raiders adding two pass rushers (Rashan Gary and Brian Burns) and a running back (Josh Jacobs) in the first round, but the Raiders really could use those three picks in a number of ways given all of their holes.