THERE IS a scene in the new film “Avengers: Age of Ultron” in which Iron Man and the Incredible Hulk go toe-to-mammoth green toe in a bit of rage-y team infighting that threatens to level entire city blocks. It’s just the sort of smackdown that also symbolizes the Avengers’ performance at the box office — because when it comes to opening weekends, the only foe who can beat this Marvel franchise is itself.

Yes, on multiple counts, the Iron Man armor continues to be the ultimate power suit. Its wearer, Robert Downey Jr., has now starred in the three biggest film openings ever — all for Marvel Studios.

“Avengers: Age of Ultron” grossed a whopping $187.7 million in North American theaters this weekend, according to studio estimates. Though final numbers are due Monday, it’s the second-best domestic debut ever. This means the film that retains its U.S. market crown with all the assurance of Floyd Mayweather is the original blockbuster in the series, “The Avengers.” The 2012 film, with its $207.4 million opening three years ago this month, remains the box-office champ, as well as the biggest superhero film of all time.

Disney/Marvel’s “Avengers” sequel wasn’t just runner-up for best weekend ever; it also had the second-best single-day domestic gross ever, totaling $84.46 million on Friday. The only film to top that: “Harry Potter and the Deathly Hallows, Part 2,” which had a one-day take of $91.07 million in 2011.

What this all boils down to is that although “Age of Ultron” couldn’t top the first “Avengers” film’s debut, as some industry analysts predicted, the Marvel Cinematic Universe still flexes the most post-“Dark Knight” muscle at the box office. After the two Avengers films, the third-biggest opening weekend ever is Downey’s “Iron Man 3,” which debuted to $174.1 million in 2013.

“It would be a shame to see headlines saying ‘Avengers 2′ fails by not setting opening-weekend records,” Phil Contrino, vice president and chief analyst at BoxOffice.com, told Variety. “This is still a massive debut.”

“Age of Ultron” has also connected with audiences around the world. Director Joss Whedon spans the globe for his story, including scenes set in Asia and Africa — a factor that surely gooses the interest further in overseas markets. “Ultron” has grossed $439 million in foreign take, bringing its worldwide total to $626.7 million already — on a $250 million production budget. (“Ultron’s” top foreign-market opening? South Korea, where part of the film is set, and where it opened to nearly $30 million.)

Together, the two “Avengers” films have now grossed more than $2 billion worldwide. The only two films still ahead of the first “Avengers” film’s $1.5 billion-plus take are by James Cameron: “Avatar” and “Titanic.”

Marvel comics continue to be the richest vein for Hollywood to mine. Since 2000, Marvel characters — including Spider-Man, the X-Men and the Fantastic Four — have grossed more than $17 billion globally on the big screen.

Further boosting Marvel’s “Avengers” franchise is its generally broad demographic appeal. About 40 percent of “Ultron’s” audience was female, according to Variety, and more than 40 percent was older than 24. Is anyone still delusional enough to insist superheroes don’t have crossover appeal?

And so, “Age of Ultron” — with Downey’s Iron Man/Tony Stark leading the assembled Thor, Hulk, Hawkeye, Black Widow and Captain America — should remain the biggest film of the year, even after Marvel’s “Ant-Man” (starring Paul Rudd) arrives in July.

There is one huge fan-based force, however, that still lurks in 2015. “Star Wars: Episode VII — The Force Awakens” lands this Christmas. And if J.J. Abrams’s Star Wars turn can top Joss Whedon’s “Ultron,” then the biggest movie star in the world, technically, would be the one actor who figures prominently in both films.

Samuel L. Jackson (aka Nick Fury/Mace Windu), you guess? Or perhaps Natalie Portman (Padme and Thor’s Jane)?

No and nope.

That would be Andy Serkis — he of the Hobbit and Planet of the Apes and Tintin franchises. “Age of Ultron” and “The Force Awakens” are his only two films out this year, but — powered by their respective geek armies — they could collectively approach $4 billion in global gross.

Go ahead and take a bow now, Andy. All the way to the bank.

FUN WITH NUMBERS:

* Six of the top 10 domestic debuts ever are superhero films, counting two “Dark Knight” films from WB/DC (holding down the fifth and sixth slots) and Sony’s “Spider-Man 3” (at No. 9).

* The only non-superhero franchise that has more than one film among the top 10 domestic debuts ever is the “Hunger Games” series — with “Catching Fire” at No. 7 and the first film from 2012 at No.8.

* Since after 2013, the only film other than “Ultron” to crack the top 10 biggest domestic debuts ever is “Furious 7,” which last month opened to $147.2 million, putting it at No. 10.