He was 24, talented and nervous. By morning, the fear of embarrassing himself on the mound had outweighed the fear of the imminent showdown against Pittsburgh sluggers Gary Redus and Bobby Bonilla, and the rest of Pirates lineup, at Olympic Stadium.
Johnson retired the first two batters he faced that day before walking Redus and giving up a double to Bonilla. In the second inning, Glenn Wilson led off with the first of two home runs in the game off Johnson. The homers taught the young pitcher a lesson he would never forget: Never, ever take it easy on a hitter.
Johnson would go on to pitch five innings against the Pirates and earn the first of his 303 career wins. Years later, another Texan would school the 6-foot-10 Johnson on the finer points of pitching. Hall of Famer Nolan Ryan, then with the Rangers, wanted the wild left-hander to throw over the top and stay in control.
On top and in control is where the one-time wild man with the wild hair would stay. When Johnson retired from baseball on Tuesday at the age of 46 and after 22 years in the game, he stepped away with awards earned, championships won and lessons learned.
The snarling figure who once intimidated hitters with a 95- to 100-mph fastball and nasty slider is at peace.
"This is something that comes along with long career," Johnson said. "Eventually, you have to say it's time."
Johnson's accomplishments are timeless. He won five Cy Young Awards and was selected to 10 All-Star teams. He racked up 4,875 strikeouts, second only to Ryan's 5,714 on the all-time list, and posted a 303-166 career record. He threw two no-hitters, the second of which was a perfect game (May 18, 2004 in Atlanta), and he won a World Series in 2001, with the D-backs.
Statistics cannot measure all of Johnson's achievements. Last season, with the Giants, he tore the rotator cuff in his throwing shoulder on July 5 but returned in September to make five relief appearances. He never felt comfortable in the role, but he was happy to be healthy and back on the mound.
"Could I play another year? I could," he said on Tuesday. "I also realize that my skills were diminishing and the bar was set high to do the things I once did. ... I really wanted to go out on my terms."
Johnson's competitiveness was a blessing and, at times, a curse. In 2006 he underwent back surgery after two seasons with the Yankees, and he admits he came back too soon after rejoining the D-backs the next season. He pitched in 10 games for Arizona that year and eventually had another back operation.
In his final season in Arizona, 2008, Johnson went 11-10 in 30 starts. He signed with the Giants that winter.
Now, about a year later, he has come to terms with his baseball mortality.
"I was very adamant about not announcing [the retirement] right away," he said. "I learned a lesson the last few years watching athletes retire and un-retire, and that's not the way I pictured retiring for myself. There were times I felt I can go out and pitch, and I could find a team that would have me in the rotation, but it comes down to performance and ability to recover after each performance."
Performance had never been an issue with Johnson. Drafted out of the University of Southern California by the Expos in the second round of the 1985 Draft, he spent almost four seasons in the Montreal organization before being traded to Seattle as part of a five-player deal on May 25, 1989.
While with the Mariners, he won 130 games and led the team in wins five times in 11 seasons. He pitched the organization's first no-hitter, became its first 20-game winner and remains the only Seattle pitcher to win a Cy Young Award.
A chat about mechanics with Ryan in August 1992 provided encouragement, and the payoff was immediate for Johnson. He finished the 1993 season 19-8 with a 3.24 ERA and 308 strikeouts in 255 1/3 innings.
In 1995, he won Game 3 of the American League Division Series against the Yankees and returned on one day's rest to strike out batters in three innings of relief, and the Mariners won Game 5 to advance to the AL Championship Series. He also won his first Cy Young Award that year.
"From '93, I really was adamant about being as focused as I could be in this game and getting the most I could out of the game," he said.
At 34 he was reminded about the business of baseball. He was traded to the Astros on July 28, 1998, for pitchers Freddy Garcia and John Halama, and Minor League shortstop Carlos Guillen. He went 10-1 with a 1.23 ERA in 11 starts for Houston. He started two games against San Diego in the National League Division Series but lost both games despite posting a 1.93 ERA.
Things got better.
Prior to the 1999 season, he signed with the D-backs and would become the greatest pitcher in the franchise's history. He won four consecutive NL Cy Young Awards and compiled a 81-27 record to go with a 2.48 ERA over that span. He was teamed with Curt Schilling from 2000 to 2003, and the pair formed the potent one-two punch that led the team to a World Series title in 2001.
Johnson made history in Game 7 of the Fall Classic. He pitched out of the bullpen to record the final four outs, and became the first pitcher in 55 years to win as a starter in Game 6 and as a reliever in Game 7.
"He was one of the greatest pitchers of all time and one of the most intimidating players of his era," D-backs general manager Josh Byrnes said. "He certainly will be an unforgettable part of Diamondbacks history."
Johnson's six-year stint in Arizona ended in 2004. He returned for two seasons starting in 2007, and he still has a one-year personal services contract with the organization.
In the end, he described his venture into retirement as equal parts joyous and sad. He doesn't know which hat he will wear when the Hall of Fame comes calling, and he's not going to worry about it.
"I never dwelled on my achievements," he said. "Maybe now I can reflect on that stuff. It would have been a distraction if I was worried about anything other than what I was doing every fifth day."
Jesse Sanchez is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.