Albert Pujols and the Angels celebrate the slugger’s 500th home run. (Photo by Jonathan Newton / The Washington Post)

When Albert Pujols sent his second ball of Tuesday night over the fence at Nationals Park, leaving Nationals right-hander Taylor Jordan slack-jawed, his teammates on the Los Angeles Angels climbed out of the dugout and met their first baseman for congratulations. Five hundred home runs is still 500 home runs, even if it feels almost commonplace now.

“That’s a lot of balls over the fence,” said Nationals Manager Matt Williams, who hit 378 homers himself.

Twenty-six players have hit 500 or more home runs. Of the 20 who are eligible for the Hall of Fame, only four aren’t in: Barry Bonds, Sammy Sosa, Mark McGwire and Rafael Palmeiro. The other 16 – those not tied, directly or indirectly, to the use of performance-enhancing drugs – have been honored in Cooperstown.

But how, ultimately, will a 500-home run hitter be judged? Pujols’s milestone last week didn’t go unnoticed. Yet so much has changed about how the accomplishment is celebrated and appreciated.

In 1998, Sosa and McGwire brought baseball back with their chase of Roger Maris’s single-season home run mark – a chase that now appears tainted. But when 1999 began, there were still just 15 members of the 500-homer club. They were the greats of the game. Depending on when you believe the majors were founded – let’s take the start of the National League, in 1876 – it took more than 120 years to get that many.

Over the next decade, 10 more members would be added – a 67 percent increase in 8 percent of the time. That includes those that Hall of Fame voters have already judged to be cheaters. There are more to come on that list – Alex Rodriguez, Manny Ramirez and Gary Sheffield – and considering the previous behavior of the Baseball Writers Association of America, which votes on the Hall of Fame, those players’ fates may be sealed.

So Pujols joins a tiny group of players who could serve as a referendum on what 500 homers means – supposedly “clean” players who reached the mark during or just after the golden age of the homer. Frank Thomas, tied for 19th overall, will be enshrined this summer. Ken Griffey Jr. will be eligible in 2016, and he seems a shoo-in. Jim Thome follows in 2018, and even though he’s just behind Griffey, his case is murkier given his status as a full-time designated hitter for his final seven seasons.

But Pujols’s homers Tuesday also represent what could be the end of the homer’s golden era. The active player closest to 500 homers without being there yet is Adam Dunn. He’s only 34 and needs 55 more, so that’s conceivable. Beyond that, though: Jason Giambi (438 homers, 43 years old), David Ortiz (436, 38), Paul Konerko (434, 38) and Alfonso Soriano (410, 38) all appear, to different degrees, to be long shots. There, then, is the proof: regardless of the era, 500 homers is still a lot of balls over the fence.