"I stand up here humbled and overwhelmed," Griffey said. "I can't describe how it feels."
The two became a piece of history on their special day. Griffey, the first pick of the 1987 amateur draft, became the highest pick ever inducted. Piazza, a 62nd-round pick the next year -No. 1,390 -- is the lowest pick to enter the Hall of Fame.
Griffey played 22 big-league seasons with the Mariners, Reds and White Sox and was selected on a record 99.32 percent of ballots cast, an affirmation of sorts for his clean performance during baseball's so-called Steroids Era.
A 13-time All-Star and 10-time Gold Glove Award winner in center field, Griffey hit 630 home runs, sixth all-time, and drove in 1,836 runs. He also was the American League MVP in 1997, drove in at least 100 runs in eight seasons, and won seven Silver Slugger Awards.
Griffey, who fell just three votes shy of being the first unanimous selection, hit 417 of his 630 homers and won all 10 of his Gold Gloves with the Seattle Mariners. He played the first 11 seasons of his career with the Mariners and led them to the playoffs for the first two times in franchise history.
"Thirteen years with the Seattle Mariners, from the day I got drafted, Seattle, Washington, has been a big part of my life," Griffey said, punctuating the end of his speech by putting a baseball cap on backward as he did throughout his career.
"I'm going to leave you with one thing. In 22 years I learned that one team will treat you the best, and that's your first team. I'm damn proud to be a Seattle Mariner."
Dubbed "The Natural" for his effortless excellence at the plate and in center field, Griffey avoided the Hall of Fame until his special weekend because he wanted his first walk through the front doors of the stately building on Main Street to be with his kids, whom he singled out one by one in his 20-minute speech.
"There are two misconceptions about me -- I didn't work hard and everything I did I made look easy," Griffey said. "Just because I made it look easy doesn't mean that it was. You don't become a Hall of Famer by not working, but working day in and day out."
Griffey's mom, Birdie, and his father, former Cincinnati Reds star Ken Sr., both cancer survivors and integral to his rise to stardom, were front and center in the first row.
"To my dad, who taught me how to play this game and to my mom, the strongest woman I know," Junior said. "To have to be mom and dad, she was our biggest fan and our biggest critic. She's the only woman I know that lives in one house and runs five others."
Selected in the draft by the Dodgers after Hall of Fame manager Tommy Lasorda, a close friend of Piazza'a father, Vince, put in a good word, Piazza struggled. He briefly quit the game while in the minor leagues, returned and persevered despite a heavy workload as he switched from first base to catcher and teammates criticized his erratic play.
Mom and dad were foremost on his mind, too.
"Dad always dreamed of playing in the major leagues," said Piazza, just the second Hall of Famer depicted on his plaque wearing a Mets cap, after Tom Seaver in 1992.
"He could not follow that dream because of the realities of life. My father's faith in me, often greater than my own, is the single most important factor of me being inducted into this Hall of Fame. Thank you dad. We made it, dad. The race is over. Now it's time to smell the roses."
Piazza played 16 years with the Dodgers, Marlins, Mets, Padres and Athletics and hit 427 home runs, including a major league record 396 as a catcher. A 12-time All-Star, Piazza won 10 Silver Slugger Awards and finished in the top five of his league's MVP voting four times.
Perhaps even more impressive, Piazza, a .308 career hitter, posted six seasons with at least 30 home runs, 100 RBI and a .300 batting average (all other catchers in baseball history combined have posted nine such seasons).
Though the Dodgers gave him his start, Piazza found a home in New York when he was traded to the Mets in May 1998.
Three years later, Piazza became a hero to the hometown fans with perhaps the most notable home run of his career. His two-run shot in the eighth inning at Shea Stadium lifted the Mets to a 3-2 victory over the Atlanta Braves in the first sporting event played in New York after the 9/11 terror attacks.
Piazza paid tribute to that moment.
"To witness the darkest evil of the human heart ... will be forever burned in my soul," Piazza said. "But from tragedy and sorrow came bravery, love, compassion, character and eventual healing.
"Many of you give me praise for the two-run home run in the first game back on Sept. 21st, but the true praise belongs to police, firefighters, first responders that knew that they were going to die, but went forward anyway."
Attendance was estimated at around 50,000 by the Hall of Fame, tying 1999 for second-most all time.