That Sosa would become the fifth member of the 600 Club once seemed inevitable, then grew into unlikely and ultimately became an inspiring surprise.
His renaissance likely caught a lot of peers off-guard, but their reactions to the historic feat slowly trickled in.
Seattle batting coach Jeff Pentland, who served in that capacity with the Cubs for a 5 1/2-year stretch that included Sosa's signature seasons, beamed while discussing his former star pupil's accomplishment.
"No, I'm not at all surprised," Pentland said. "My first experience with Sammy was the first time I saw him up close and personal. I had seen him from the other side, but I realized he was the complete package. He had power and speed, which is a rare commodity. Sammy had both.
"I think the biggest thing with Sammy and I is we were joined at the hip," added Pentland. "We spent a lot of time together in batting cages. We are also very good friends, and that kind of made it easy. I had to motivate him in his [1998 home run] race with [Mark] McGwire."
Sosa doesn't regard No. 600 as a finish line. If anything, it feels to him like the springboard to another career, one devoid of the pressures to reach the rare number.
Others agree that Sosa may have a lot to give -- and to get.
"As long as he's productive, he can keep on playing," said Cubs first baseman Derrek Lee. "He's not the Sammy Sosa of six, eight years ago. But he's productive. He's got the homers and RBIs. Any team would take that. If he can do that, he can play, simple as that."
The Sosa salutes shouldn't go overboard on his return to the spotlight after a year's sabbatical from the game. Others have resurrected careers, under direr circumstances. Most notably, Ted Williams twice had to readjust, following military service in World War II and then Korea.
For all intents and purposes, Sosa had merely been embarrassed out of the game, after swinging-and-missing through much of the 2005 season in Baltimore, where he had wound up following his messy split with Chicago's North Side.
He went 611 days between home runs, from his final trot as an Oriole on Aug. 4, 2005, to his return blast with the Rangers on April 7.
No one has a better insight into that dry spell than Washington bullpen catcher Julian Martinez, who was a confidante of Sosa while serving the same role with the Cubs from 1998 to 2004.
"I'm really happy for him, especially after what he went through. He has 600, so now he is going to be more relaxed," Martinez said. "I'm going to celebrate for him.
"It's more mental than physical. He took a year off, and he came back prepared -- physically and mentally."
Seattle first baseman Richie Sexson shook his head when contemplating 600. At 32, he has good reason to be impressed: Sexson has had two seasons of 45 homers and four other times has reached the 30s, yet his career total stood at 285 the night Sosa went 600.
"That's a lot of home runs," Sexson said. "To hit that many is amazing, and there are only a handful of guys who have done it. It puts himself in an elite class. When I was with Milwaukee [2000-03], he hit a lot of homers against us. He must have hit 25 or 30 against us when I was there."