Star edge rusher Khalil Mack (52) is bound for Chicago. (Photo by Norm Hall/Getty Images)

Players like Khalil Mack aren’t supposed to be traded. Not in the NFL. Not in a league in which drafting good players and then developing them always has been the surest path to success. Not under an economic system in which a team can extend a prized rookie’s contract to five years and then utilize the franchise tag for a few seasons after that.

But Mack indeed has been traded, in a once-unlikely deal that changes the on-field direction of two franchises and the playoff outlook in both conferences. The Oakland Raiders agreed Saturday to send Mack, the standout pass rusher and former NFL defensive player of the year, to the Chicago Bears for a package that includes two first-round draft choices, according to a person familiar with the situation who confirmed multiple reports of the trade.

The trade was accompanied by a new contract for Mack with the Bears that makes him the NFL’s highest-paid defensive player. Mack’s six-year, $141 million deal includes about $90 million in guaranteed money, according to the person with knowledge of the deliberations, and surpasses the six-year, $135 million extension that defensive tackle Aaron Donald, the reigning NFL defensive player of the year, just signed with the Los Angeles Rams.

The Raiders receive first-round picks next year and in 2020 in the trade, along with a third-rounder in 2020 and a sixth-rounder next year. The Bears, in addition to Mack, get a second-round selection and a conditional fifth-rounder, both in 2020.

Donald’s contract agreement with the Rams, which included $87 million in guaranteed money, set the market for Mack. But instead of signing Mack to a comparable deal, the Raiders and their new coach, Jon Gruden, shipped him off, leaving a team coming off a 6-10 season without its best player.

“With a change like they had at head coach, I would say that anything could be possible,” a front office executive said in recent days of the possibility of a Mack trade, “especially because of the way it sounds like the relationship already is.”

Perhaps this is, at least in part, an economic decision by the Raiders, as some have speculated. They are reportedly one of the league’s poorer franchises, and they’re about to leave the Bay Area for Las Vegas. They have handed out a series of significant contracts to players, including a five-year, $125 million deal to quarterback Derek Carr. They lured Gruden back to the sideline from ESPN’s “Monday Night Football” broadcast booth with a contract said to be worth $100 million over 10 years.

But from a football standpoint, it seems to signal that Gruden does not believe the Raiders are ready to win now. Instead, the Raiders will use the multitude of draft picks they are receiving from the Bears to attempt to put a contender on the field around the time they arrive in Vegas, which is expected to be in 2020. Gruden and the Raiders might try to spin it otherwise. Gruden mentioned at one point that the team’s defense wasn’t very good last season even with Mack. But a team trying to accomplish big things in the near term does not willingly part with a player of Mack’s caliber.

He is a three-time Pro Bowl selection in four NFL seasons. He has 40.5 sacks in his career. He once was named first-team all-pro at two positions, defensive end and outside linebacker, in the same season. He was the league’s defensive player of the year in 2016. He also plays a position, edge rusher, that is considered perhaps the most valuable in the sport after quarterback.

Former NFL player, scout and front office executive Louis Riddick, now an NFL analyst for ESPN, wrote on Twitter: “No logical reason for [the Raiders] to make this ‘football’ move. No salary cap reason either. This has to be a cash issue. You do not let guys like [Mack] out the door. Their loss is [the Bears’] gain.”

Raiders linebacker Bruce Irvin was even more succinct in his social-media reaction. Irvin wrote on Twitter, apparently in reference to the trade: “No [expletive] way.” He later wrote: “What a shock. Now move on and win … time to beat the Rams [in the season opener]!!”

Mack was to make $13.846 million this season under the fifth-year option in his rookie contract previously exercised by the Raiders. He wanted a new contract and was holding out to get it. The circumstances were nearly identical to those of the Rams and Donald. But while the Rams maintained constant dialogue and kept negotiating with Donald and his agents until striking a deal, the Raiders and Mack’s representatives had little to no contact.

Mack is getting his contract. But it is coming from the Bears, not the Raiders. The move vaults the Bears into the conversation in the NFC North. The Minnesota Vikings added quarterback Kirk Cousins in the offseason to a Super Bowl-ready team. The Green Bay Packers have back a healthy Aaron Rodgers and just made him the NFL’s highest-paid player. The Detroit Lions have a new coach, Matt Patricia, who inherited a team coming off a winning season and a franchise quarterback in Matthew Stafford.

The Bears might have been left behind. They did hire a new coach in the offseason, Matt Nagy, and are hoping he can do for their young quarterback, Mitchell Trubisky, what Sean McVay did for Jared Goff and the Rams last season. But that alone probably would not have made Chicago a contender.

Now, though, the Bears have added a true difference-maker on defense. The trade for Mack changes everything. Suddenly, it’s conceivable the Bears could be in the playoff mix in the NFC. They could be on the heels of the Vikings and Packers in the division, not just this season, but longer-term. Mack is that good.

If Trubisky develops as the Bears hope, suddenly Chicago has young cornerstone players on both sides of the ball who can allow it to compete with Minnesota and Green Bay, both of which are set up for success over the next several years. The cost may be high. But to hang with those two teams, bold moves were likely going to be necessary. This trade is as bold as it gets.

These things do happen in the NFL. Defensive tackle Sean Gilbert once sat out an entire season, in 1997, in a contract dispute, leading the Washington Redskins to trade him to the Carolina Panthers.

But they don’t happen very often at all. And when they do, they shake up the natural order of things in the NFL. That’s exactly what took place Saturday.

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