Barry Bonds' single-season record of 73 home runs has stood for 19 years. His career record of 762 home runs, for 13.

And counting. Possibly for a very long time.

As we continue with Steroid Week here at B/R, we're frankly not interested in relitigating how Bonds became the greatest home run hitter in the history of Major League Baseball. Specifically with regard to the 317 homers he hit between 2000 and 2007, it was part extraordinary natural talent and part performance-enhancing drugs. Regardless of how that makes you feel, that's the basic reality.

At this point, a more interesting question is whether the former San Francisco Giants slugger's signature marks of 73 and 762 will ever be broken. 

It's a safe guess they will be eventually, but the only basis for that is the notion that "records are made to be broken." At least on an individual level, the current state of baseball isn't conducive to new home run records. 

This might seem counterintuitive in light of how frequently balls were flying over fences in 2019. The season set a record with 6,776 total home runs, demolishing the old record of 6,105.

But unlike with the home run surges of the 1990s and early 2000s, this didn't happen because a select few guys suddenly hit a lot more home runs. Even in leading the league with 53 homers, Pete Alonso still finished 20 shy of Bonds' record. The dinger deluge was more of a group effort, as a record 129 players went deep at least 20 times.

That speaks to how, largely by way of recent advancements in batted ball data, swinging for the fences is now the default mode for many hitters. Yet the degree of difficulty for individual sluggers to separate themselves from the pack also speaks to how times have changed since 2001.

When Bonds hit 73 homers, it wasn't because he was bigger and stronger in 2001 than Mark McGwire was when he hit 70 in 1998. McGwire turned batted balls (simplified here to non-strikeout at-bats) into home runs at a 19.8 percent clip in '98. In '01, Bonds did it at a rate of 19.1 percent. 

The difference was that Bonds wasted fewer at-bats on strikeouts. Whereas McGwire whiffed 155 times in '98, Bonds fanned only 93 times in '01. He thus put more balls in play, which ultimately allowed him to leapfrog McGwire even though his batted balls didn't clear the fence as often.

This is not to suggest that Bonds was a particularly gifted contact hitter. For the 2001 season, his strikeout rate of 14.0 percent only tied for 70th among qualified hitters.

But if that strikeout rate were transported over to 2019, Bonds would have tied Anthony Rizzo and Nolan Arenado for 21st among qualified hitters. That's emblematic of how strikeouts have rapidly increased since 2001, which itself is part of a longstanding trend:

The rising tide of strikeouts hasn't altogether killed extreme home run seasons. To wit, there have been 12 seasons of 50-plus homers since 2001.

Yet the strikeouts do help explain why nobody has made it to even 60 home runs since 2001. Ryan Howard came close in 2006, but his 25.7 K% stopped him at 58 long balls. Giancarlo Stanton came even closer in 2017, but his 23.6 K% stopped him at 59.

Somebody like Cody Bellinger, who hit 47 homers with only a 16.4 K% in 2019, might have a shot at hitting 74 homers in a season. But even he would have to lower his strikeout rate and improve his efficiency at turning batted balls into homers. His homers-per-batted-balls rate in 2019 was only 10.4 percent, about half of what Bonds achieved in 2001.

So setting aside the possibility of some kind of messianic super-hitter coming out of nowhere, the eventuality of a 74-homer season hinges on changes to baseball's environment. Either the strikeout rate will have to come down or the home run rate will have to keep going up.

Frankly, these are hard things to count on.

The recent proliferation of home runs has almost certainly been born out of a juiced ball, and that experiment would be better ended than continued. De-juicing the ball could get hitters to change their habits and try to put more balls in play, but neither that nor any possible rule changes can undo arguably the biggest underlying reason for the rising strikeout rate: modern pitchers throw really hard.

But what of Bonds' all-time home run record?

To hit as many as 763 home runs, a hitter wouldn't have to hit 74 or more home runs in any single season. To wit, he would merely need to average 38 homers per season over a 20-year career. That's potentially doable even if the ball gets de-juiced and strikeouts continue to rise.

The key, however, would be for said hitter to age gracefully. That goes against another trend, in which younger hitters are more drastically outperforming older hitters in the 30-team era:

Jeff Zimmerman of FanGraphs was on this as far back as 2013, when he observed that the aging curve for hitters was shifting from generally being in favor of veterans to favoring up-and-coming 20-somethings. Obviously, not much has changed since then.

This partially comes down to how younger hitters are simply better than they used to be. But it's also reflective of how much harder it is for older hitters to stay relevant now that they don't have PEDs to fall back on as their bodies begin to break down.

Consider Albert Pujols. The 40-year-old has now played in more games after the age of 30 (1,424) than he did beforehand (1,399), but he hit 76 more homers in his 20s than he has since then. Even if the coronavirus hadn't come along this year, it's doubtful that he would have closed the gap between those two figures before his contract with the Los Angeles Angels ran out in 2021.

If there's hope for older hitters somewhere in the near future, it's the likelihood that the designated hitter will soon be universal. Just as it did for David Ortiz, Frank Thomas and Edgar Martinez, the position would help more hitters stick around if it indeed makes its way to the National League.

Otherwise, it's hard to imagine any upcoming developments that might make it easier for an older slugger to stick around long enough to break Bonds' career home run record. Somebody's basically going to have to be the next Hank Aaron, except better and longer-lasting.

This is where it's worth reiterating that 73 and 762 probably will fall eventually. Neither mark seems as wholly unbreakable as, say, Cy Young's 511 wins. There's also the reality that forever is a long time. It's hard to know what baseball is going to look like even 10 years from now, much less 20, 30, 40 and so on.

But ultimately, anyone who assumes Bonds' records will be broken shouldn't sit back and wait for that to happen. Chances are it's going to be a long wait.

Catch Up on B/R's Steroid Week:

Mon: McGwire vs. Sosa in '98

Tues: Will Bonds' Records Ever Be Broken?

Wed: Most Ridiculous Seasons of Steroid Era

Thurs: How A-Rod Survived Steroid Hell

Fri: Which Steroid Users* Should Be in HOF?

Stats courtesy of Baseball Reference and FanGraphs. Videos courtesy of MLB, via YouTube.