The Herschel Walker trade ranks as one of the biggest steals in NFL history, with the Dallas Cowboys turning the bundle of draft picks donated by the Minnesota Vikings into the foundation for a dynasty.
But it was the Charles Haley trade a few years later that swung the balance of power in the NFL.
That's still a sore point for some of Haley's former teammates with the San Francisco 49ers, whose front office wanted to get rid of Haley despite the pass-rusher having played a major role on two Super Bowl winners. Jerry Jones gave up two draft picks (second- and third-rounders) to win three championships.
"I cannot believe we traded this guy," legendary former 49ers receiver Jerry Rice said recently. "We probably would have won two or three more."
Haley's statistics are those of a borderline Hall of Fame player. He had 100.5 sacks in his injury-shortened career -- or two fewer than former Cowboys defensive end Jim Jeffcoat, a fine player but one whose name never comes up in discussions about the all-time greats. Haley made five Pro Bowls and twice was voted the NFC's defensive player of the year.
Haley's impact, however, screams Hall of Fame.
No other player owns five Super Bowl rings. And Haley, a Hall of Fame finalist for the second straight year, wasn't just along for the ride in those games. He had 4.5 sacks in his five appearances on football's biggest stage.
The Cowboys were a talented young team whose core had one playoff win when they traded for Haley, who had worn out his welcome in San Francisco with his wild mood swings and occasionally vile behavior. Dallas became a dynasty after that deal, winning three Super Bowls in four seasons before Haley's bad back forced him into early retirement.
"Jerry said, 'We couldn't spell Super Bowl without Charles Haley.' I would agree with that," Hall of Fame quarterback Troy Aikman said. "I don't think we do anything even close to what we accomplished without him.
"I am surprised that he has not been voted into the Hall of Fame at this time, because he was an integral part of all five of those world championships he was a part of. He wasn't just on the roster or a role player. He was a major reason why."
The Cowboys morphed from a mediocre defense to a dominant one after acquiring Haley. Dallas ranked 17th in total defense in 1991, when the Cowboys' season ended with Detroit Lions quarterback Erik Kramer passing for 341 yards and three touchdowns in a divisional round rout. Dallas led the NFL in total defense the next season.
There is nothing coincidental about that.
"Charles was that guy who brought the dog, who brought the fight to the table and changed the whole perception of what it was to play defense for the Dallas Cowboys," said former Cowboys safety Darren Woodson, who also deserves serious Canton consideration. "It was speed, speed, speed. Now we had some fight in us. Now we'd bite you."
Haley, who was diagnosed with bipolar disorder after his career ended, certainly had some issues after he left San Francisco for Dallas. He didn't do himself any favors with his often crude treatment of the media. (Haley did not respond to repeated requests to be interviewed for this column.) He had a few heated run-ins with head coach Jimmy Johnson. And he wasn't always a treat for teammates, either, to put it mildly.
But ask anybody who wears a Super Bowl ring from XXVII, XXVIII or XXX and they'll express great appreciation for Haley.
"I love the guy to death," Aikman said. "He was a consummate professional in my opinion. He wasn't always during the week, but boy on Sunday, he sure was."
On Saturday, after the vote is taken, Haley ought to be a Hall of Famer.
Tim MacMahon covers the Cowboys for ESPNDallas.com. You can follow him on Twitter.