Aaron Judge, left, and Cody Bellinger are the home run hitting titans among rookies this season; Judge won the Home Run Derby on Monday night. (Rob Carr/Getty Images)

The Houston Astros and Los Angeles Dodgers appear unbeatable. The Chicago Cubs appear lost in a post-World Series fog. The Washington Nationals need a closer, the New York Yankees a first baseman, the New York Mets a wrecking ball. Bryce Harper is great again. Aaron Judge is a phenomenon. Mike Trout is hurt (but on his way back). Max Scherzer may be the best pitcher in baseball at this very moment — on the eve of his start Tuesday in the All-Star Game — but Clayton Kershaw still has something to say about that. Amazingly, Bartolo Colon still has a job.

And yet, the most inescapable story line in baseball at its annual midseason break is neither a team nor a player, but an action. The biggest story in baseball in 2017, by far, is the home run. It was so Monday night, as some of the game’s top sluggers took aim at the Marlins Park bleachers during that annual celebration of the long ball, the Home Run Derby. It will be so Tuesday night, as the 88th All-Star Game is played. And it will be so still on Friday, when the second half of the season, with all its promise of pennant races and record chases, gets underway.

At the close of the first half, baseball found itself on pace for 6,127 homers this season, which would shatter the record of 5,693, set in 2000 at the height of the so-called steroids era. June alone brought 1,101 four-baggers, the most for any single month in baseball history.

Judge, the Yankees’ mammoth right fielder, has 30 homers, the most by a rookie at the all-star break since Mark McGwire had 33 in 1987. Another rookie, Cody Bellinger of the Dodgers, has 25. Someone named Scott Schebler has 22. Someone else named Scooter Gennett hit four in a game. Thirty-six homers have been measured at 460 feet or longer this season, including a 467-footer struck by a pitcher, Colorado’s Jon Gray.

The topic of home runs was inescapable Monday, as the all-stars from the National and American Leagues met the media on the warning track of Marlins Park, and as a near-sellout crowd gasped and oohed at the spectacle of Judge (6-foot-7, 282 pounds) and hometown favorite Giancarlo Stanton of the Miami Marlins launching balls into the furthest reaches of the stadium during the derby. Judge won the contest by beating Minnesota Twins slugger Miguel Sano, 11-10, in the final, and Judge had the night’s longest drive, a 513-footer.

Even in the quieter, private moments the players shared among themselves, the subject of home runs was front and center: “We were just talking about this five minutes ago [during] the team picture,” said Houston Astros lefty Dallas Keuchel.

Everyone is affected by the spike in home runs, from the hitters who are slugging them to the pitchers trying to avoid giving them up.

“The ball is flying, for whatever reason. I really don’t care,” said Scherzer, the Nationals’ ace right-hander. “I’ve given up a lot of homers over the past year and a half. That’s really been something that’s been a thorn in my side. I’ve had to become a better pitcher, locate better. Because of the home run spike, I’ve dialed it in even more to try to make my location better to try to prevent them.”

There are obvious, incremental trends in baseball that help explain the homer surge. Clearly, the game is evolving in the direction of power, with pitchers’ average velocity climbing for 10 straight seasons, to 92.8 mph this season, and hitters armed with launch-angle and exit-velocity data learning how to maximize ball flight. According to data at Fangraphs.com, the rate at which flyballs become home runs has increased in every season since 2014, from 9.5 percent that year to 13.7 percent so far in 2017. With the increase in home runs has come a corresponding increase in strikeouts, with a record 21.6 percent of all at-bats this season ending in a strikeout.

“I don’t know if it’s the velocity or the change in approach of hitters, or maybe both,” Kershaw, the Dodgers’ ace left-hander, said. “But strikeouts are up, home runs are up, and pitchers are throwing harder. So they’re all probably connected at some point.”

The all-or-nothing approach is perhaps best personified by Texas Rangers infielder Joey Gallo, who has 112 strikeouts in 248 at-bats this season, with more home runs (21) than singles (14), all while batting just .194. But there are less extreme versions of Gallo up and down big league rosters.

“A lot of younger players are coming up, and they’re not necessarily concerned with strikeouts,” San Francisco Giants catcher Buster Posey said, “so they’re taking an aggressive hack with two strikes, which is going to lead to more balls leaving the park.”

But pitchers in particular are finding it increasingly difficult to shrug off the rise in home run rates as a product of a changing approach. And more than ever, it is the baseball itself that is coming under scrutiny, with a rising number of pitchers claiming the composition and/or size of the ball has changed this year. Many have said the seams are noticeably lower — which, at least theoretically, could cause balls to encounter less drag as they fly through the air, and thus fly farther.

“You can make a case for yes, they’re juiced, or no, they’re not,” Keuchel said. “I mean, nobody’s going to know. I personally think . . . they are.”

Conspiracy theories about “juiced” balls have long been a part of the sport at various points in its history, but perhaps never with so much consensus.

“We could all sit here and say the ball is smaller or juiced or [more tightly] wound, whatever it may be,” Detroit Tigers right-hander Michael Fulmer said. “[But] when you’ve been playing the game as long as we have as pitchers, and a ball comes off the bat, and you see the trajectory of it, the sound of it, you say, ‘Okay, that’s a routine flyout.’ And I’ve seen that ball get over the fence this year.”

As recently as 2014, scoring in baseball was at a 30-year low. But almost overnight, around July 2015, balls began leaving stadiums at a noticeably higher rate. Recently, studies conducted by the websites TheRinger.com and FiveThirtyEight.com both concluded that the ball has changed, with the former finding this year’s ball has lower seams and smaller circumference than ones from the first half of 2015, and the latter finding these new balls are flying further.

Major League Baseball has insisted the ball has not undergone a fundamental change, going so far as to release a statement to both the media and the players saying it regularly tests the baseballs, and that the current batch conforms to the same set of standards it has always used, saying there was “no evidence” the composition of the ball has changed in 2017.

“Major League Baseball said it isn’t [different], so there you go,” Kershaw said, with perhaps a trace of sarcasm. “Maybe we just need to pitch better.”