One of the Big Hurt's teammates, though, has been around the game long enough to see Thomas' entire career. Jays shortstop Royce Clayton was drafted a year before Thomas, and made his Major League debut one year after Toronto's slugger.
Clayton's historical knowledge of the game runs deep, as does his appreciation for what Thomas has been able to achieve over his 18-year career.
"A lot of these guys don't remember how Frank, in the early 90's, was the dominant player in this league," Clayton said. "Even though he's 39, he's still doing it. He hit 39 home runs last year at an age where a lot of people his age are dropping off substantially -- especially power hitters. To remain that consistent says a lot about his dedication."
Clayton was teammates with Thomas during the 2001-02 seasons in Chicago, and the two veterans were reunited for the second time when they signed free agent contracts with the Jays over the offseason. Even though the game has changed dramatically since they entered the league, Clayton is quick to shoot down any talk that the 500 Home Run Club doesn't hold the same kind of prestige that it once did.
"500 is 500," Clayton said. "That's an automatic trip into the Hall of Fame. If you can't appreciate that in this day and age, then I think people are missing out, because besides from a few, we're not going to see it too much more. ... The guys who do hit 30-40 home runs a year, you don't see them having that type of consistency and longevity that Frank has had."
Jays manager John Gibbons said Thomas' achievement Thursday in Minnesota was something few other players have done, and that he would like to believe that Thomas' 500 career home runs put him in the Hall of Fame.
"I sure hope so. I mean, [baseball writers] vote, not me, but I sure hope," Gibbons said. "It's a great accomplishment, only 21 guys have done that. First of all, to have longevity in this game, to play as long as he's been playing and then to maintain that level of play, that speaks for itself."
Jays reliever and Chicago native Jason Frasor was just 13 years old when Thomas first homered in the Majors. The right-hander grew up as a fan of the Cubs, but he says now that he is older, he has learned to appreciate all that Thomas has done for the game.
"You grow up and you learn to respect the player and his achievements," Frasor said. "He was amazing. Two-time MVP. I didn't care for him back then, because of the Cubs, but I love him now. He's a great teammate, and he deserves all the milestones he's reached in his career."
What impresses Frasor the most is the longevity Thomas has sustained in his career. Thomas, who is listed at 6-foot-5, 275 pounds, has been placed on the disabled list six times over 18 seasons, and has been forced to undergo countless surgeries on various parts of his body. But each and every time, he's managed to come back with his classic power stroke that has helped cement his place among baseball's elite.
"It's incredible," Frasor said. "He's worked really hard to keep his body in shape and get back from those injuries. I'm going on four years and it feels like 20. I don't know how he's done it."
Thomas was also the boyhood hero of Jays 23-year-old left fielder Adam Lind. While Lind was growing up in Muncie, Ind., he used to make the trip to Chicago to watch Thomas in person.
"I loved watching Frank," Lind said. "I think he was a favorite of a lot of kids, just because he was so big and hit so many home runs. ... Now he'll be in the record books. Five-hundred is one of those milestones in baseball that proves greatness."
For Clayton, he's just happy Thomas now has his place in history, but he hopes that's not all people will remember Thomas for.
"Five-hundred home runs is one thing," Clayton said. "But if you look at his career on-base percentage, slugging percentage, batting average, it's really impressive. For a man of his stature to combine all that together, it's an accomplishment to the dedication to his craft and his professionalism."
Thomas said that even though he has spent just half a season with the Blue Jays, his teammates have been supportive during his quest for No. 500, and he appreciates that.
"They've been great. They've been encouraging," he said. "They know how hard its been to get here."
Gregor Chisholm and Joe Kieser are contributors to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.