Bobby Beathard, the San Diego Chargers general manager, said: "It's tough when you get it going like that to lose a guy like Johnson. I know how players react to things."
And the Cowboys players don't appear to be happy about the news.
Wide receiver Michael Irvin, who played for Johnson in college, stormed through the team's training facility yesterday and later said, "Of course, I'm upset about it."
Told Johnson had said he had lost his ability to give 100 percent of himself to the job, Irwin replied, "I'll take 50 percent of him rather than 100 percent of most coaches."
Offensive lineman Kevin Gogan, a free agent, said flatly: "This makes me rethink about my intentions of coming back to the Cowboys."
Quarterback Troy Aikman, who earlier said he wouldn't have signed an eight-year contract if he knew Johnson might leave, said, "It's unfortunate, no question about it."
Opposing coaches also know it'll be tough on the Cowboys.
Dan Reeves, of the New York Giants, said: "I think it will have an impact. I always thought they were one of the better-coached teams."
Even Buddy Ryan, the Arizona Cardinals coach who used to brag he never lost to Johnson, saluted him.
"I'm disappointed. . . . We'll still have great competition with Dallas, but it won't be the same without competing against Jimmy," he said.
The Philadelphia Eagles' Rich Kotite, who's now the senior coach in the NFC East with three years on the job, said, "It's sad. This is a tough enough business when you lose, let alone to have to go through things like this when you win."
Chicago Bears coach Dave Wannstedt, who coached undeJohnson in Dallas, said, "It won't be an easy job [to replace Johnson], but it wasn't an easy job when we took over, either."
Television analyst and former NFL coach John Madden said Johnson's departure surprised him.
"Back in December, we were talking to Troy Aikman right after he signed his contract and he said the only thing that bothered him was the eight years. He knew Norv Turner wouldn't be there for eight years, but he hoped Jimmy Johnson would stay. Later, I told that to Jimmy, and he just laughed."
The Washington Redskins certainly won't miss Johnson, though.
When he went 1-15 in 1989, his lone win came in Washington. In 1991, when the Redskins were 11-0, the Cowboys beat the Redskins in Washington to cost them a bid for a perfect season.