Hoffman, 37, got his 400th on Friday night against the St. Louis Cardinals, accomplished the feat in the second month of his 11th season as a full-time closer.
Smith, the all-time leader in saves with 478, reached that lofty number at the age of 39 in his 18th big league season.
Franco, now serving as a Houston setup man at the age of 44, hasn't been a full-time closer since 1999, when he was with the New York Mets, but he had already done enough in 16 years before then to land at his current total of 424.
After Hoffman, it's a long way down the list to the active full-time closer with the most saves, Mariano Rivera.
Rivera, who some consider the best closer ever because of his dominant playoff performances, ranks eighth all-time with 339 saves. He took over the Yankees' role in 1997, which means he's averaged about 42 saves per year, including a career-high of 53 in 2004.
At that rate, he'd get to 400 sometime next year, which would be good because he'll be 36 by then.
Rivera said he was thrilled to hear about Hoffman's accomplishment.
"That is definitely huge," Rivera said. "A good milestone to reach. I'm not even thinking that far down the road."
"It's tough to say [if he can do it]. Four hundred is a big number. We won't see that many do it. That's a lot of pitching. You have to do it at a high level for many years. Getting from 300 to 400 may be the toughest stretch."
That's a good way to look at it, according to veteran closer Eddie Guardado, who pitches for the Seattle Mariners.
"There are so many things that have to work out to be that good for that long," Guardado said. "Think about it. That's a lot of saves. You have to stay healthy. That's the main thing. And your team has to win a lot of games for you to get the opportunity to get those saves."
Troy Percival, who spent the first 10 years of his career with the Angels but plies his trade for the Detroit Tigers now, would figure to be the next in line after Rivera, since he's got 318 saves and he'll turn 36 in August.
Percival was diagnosed with degenerative hip changes in 2003 and had elbow problems in 2004, but he still notched 33 saves in each of those seasons. Now he's on a team that's rebuilding after a string of losing seasons.
Next in line might be Jose Mesa, the Pittsburgh Pirates closer who keeps on ticking. He'll turn 39 in May but just recently passed the coveted 300 mark.
He's already got 10 this year and has averaged more than 38 saves the previous four years, so if he continues at his pace, he'll get 400 if he's still pitching at the age of 42 in early 2008.
"I don't know how much longer Jose Mesa is going to play, but I believe if he keeps pitching, he can get 400," Texas closer Francisco Cordero said. "Mariano is not one
of the best closers in baseball, he is
the best. I know he can get more than 400."
Billy Wagner of the Philadelphia Phillies had his 2004 season cut short by injuries and nailed down only 21 saves last year, but he's at 252 for his career and he hasn't turned 34 yet, so he's got a shot.
Jason Isringhausen of the St. Louis Cardinals began his career as a New York Mets starter before committing to closing full-time in 2000 with the Oakland A's. Since then, he's amassed 184 saves. Not bad when you notice he hasn't yet turned 33.
Still, that means he'll have to get 216 more saves, which will take him another six seasons at his present pace. And considering Isringhausen is on the 15-day disabled list with a right abdominal strain, his pursuit of 400 is at least on temporary hold.
After that, it's basically a crapshoot based on a few things, according to Guardado, who, by the way, has collected 142 saves since assuming the full-time role with the Minnesota Twins in late 2000.
"As far as young guys go, you look for dynamic pitches and good teams," Guardado said. "And again, they have to stay healthy."
Some of the closers who could eventually contend are fireballer Cordero, 23-year-old first-year closer Francisco "K-Rod" Rodriguez of the Angels and hard-throwing Brad Lidge of the Astros.
But Los Angeles Dodgers closer Eric Gagne was the first one Guardado mentioned when asked about contenders from the younger set, in part because of Gagne's unbelievable Major League record of 84 consecutive successful saves.
Gagne is 29 years old and has been the Dodgers' full-time ninth-inning guy only since 2002, but he's already been credited with 152 saves, so he's averaging over 50 per season, which would get him there in another five years.
"He's got to be the one from the younger guys," Seattle reliever Ron Villone said. "I mean, 80-something in a row? That's pretty good, isn't it?"
Surely Trevor Hoffman thinks so.