His two seasons with the New York Yankees were trying. But Johnson said they were worth it, even though he never won a World Series ring there, as he did with the Diamondbacks in 2001.
"I'm very excited about being back here," Johnson said Tuesday during a news conference in Chase Field's home clubhouse. "The run that I had, as short-lived as it was, as well-documented as it was in New York, I wouldn't change a thing. I think those are life experiences that make a man. I made some mistakes there; I 'fessed up to the mistakes that I made. On the field, I gave everything I had."
Arizona is betting that the rangy 43-year-old left-hander has a lot more left to give. The Diamondbacks gave him a $26 million, two-year contract and traded right-handed reliever Luis Vizcaino and three minor-leaguers to the Yankees: right-handers Ross Ohlendorf and Steven Jackson and shortstop Alberto Gonzalez.
"A lot of people say my career is over," Johnson said. "I had a 5.00 ERA. Well, I was out there pitching with a bad back for most of the year.
"Most people may not choose to do that, but I decided that's the kind of person I am," he added. "Overpaid athlete that wants to try to give something back. I know it sounds kind of corny, but that's where I'm at."
New York also agreed to pay $2 million of Johnson's salary this year. Because of the cash involved, the deal had to be approved by commissioner Bud Selig.
"We're trying to change how we do business, and the last two years have been a full-court press on that," Yankees general manager Brian Cashman said. "I'm trying to speed up the process of getting younger, getting more flexible and getting more athletic.
"I'm happy about the inventory we're collecting," Cashman said.
Johnson, who had back surgery in October, passed his physical on Monday and waived his no-trade clause to accept the deal. He said he plans to begin playing catch next week but wasn't sure when he might start throwing off a mound.
"My back is recovering great," he said. "Am I going to be ready for Opening Day? I'd like to think so, but I'm not going to say I am."
In a meeting before his news conference, Johnson endorsed manager Bob Melvin's plan to start Brandon Webb, last year's NL Cy Young Award winner, on Opening Day.
The Diamondbacks hope Johnson will help them end a three-year streak of losing seasons, the longest in their nine-year history. He joins a rotation that is anchored by Webb and includes veterans Livan Hernandez and Doug Davis.
"We are ecstatic to bring Randy Johnson back home to Arizona," general manager Josh Byrnes said.
Johnson is happy to return to the Phoenix area, where he maintained a home after being traded to the Yankees. His best seasons came in Arizona, where he went 103-49 in six seasons and won four NL Cy Young Awards before going to the Yankees in a trade he sought two years ago.
The road back was paved when Cashman called Johnson last month to express condolences on the death of his brother.
"Out of a genuine condolence call and genuine concern, Brian asked Randy if he could reach out to a couple of clubs closer to home, and Randy said he could do that, and that led us to where we are today," said Barry Meister, one of Johnson's agents.
Cashman insisted Johnson never asked to be traded.
"I think it was clear that he would prefer to pitch somewhere else but understanding that it had to make sense for us," the GM said. "He wasn't saying he didn't want to be in New York."
Cashman admitted the deal was a gamble.
"By making a move here with Randy Johnson, I do put the rotation at risk," he said. "We'll take a half-step back hopefully to take two steps forward with the greater inventory that we have to turn to and the competition that that inventory can have amongst each other.
"What we're talking about here are prospects," he added. "I recognize that means they're suspects at the same time."
Johnson posed with his old No. 51 in the Diamondbacks' new red-trimmed home uniforms, and he seemed more relaxed than he was for much of his time in New York. Even before he officially became a Yankee, Johnson got into a sidewalk confrontation with a television cameraman while walking from his hotel to his physical.
"This was a little bit more to deal with than maybe some of the other places," Cashman said. "Not just the playing aspect of it -- the coverage clearly and the attention, everything is more magnified in this town, and obviously the expectation levels are sometimes higher than anybody can ever reach."
Johnson won 34 games for the Yankees but none in the postseason, and he became expendable as the Yankees stockpiled starting pitching. Although Johnson didn't become a fan favorite in New York, he said he "never got the feeling" that Yankees fans wanted him gone.
"If you don't pitch well there, they're going to voice their opinion," he said. "I've always understood that as a professional athlete.
"As a consumer myself, when I buy a steak or go to the movies, if it's not a good steak I send it back and if it's not a good movie I usually leave," Johnson said. "If I didn't pitch well there, they'd boo me. I've been booed here in a Diamondback uniform. It's completely understandable. That didn't bother me."
But Johnson bristles at the notion that his back problems have reduced him to mediocrity. He flashed some of the attitude that has made him a tough interview and a tougher pitcher over the years.
"Ten years ago, I had back surgery, and they thought my career was over then," he said. "When I walk around with a chip on my shoulder, it's been an uphill battle. I've always had to prove my worth, I guess you would say, much like now."
Johnson needs 20 wins to reach 300. If he reaches the milestone, he'll do it as a Diamondback.
"Even if I was healthy, I may not be able to win 20 games" this season, Johnson said. "And hopefully, having the security of being here again [in 2008], that would assure having at least 300 wins, if not more."