Both Marvel movies have very good reviews and a rabid fanbase, but only one will be king of the domestic box office.

Will “Avengers: Infinity War” reach the level of “Black Panther” in North America? Three months ago, that question would be sacrilege. However, In its tenth weekend, “Black Panther” is still in the top 10, where it likely remains for at least one more weekend; it should end up around $700 million domestic gross, $1.360 billion worldwide.

Almost certainly, “Avengers” will best “Black Panther” in worldwide gross. “Black Panther” made about $650 million overseas, but recent top Marvel releases, including “Avengers: Age of Ultron,” saw about a 65/35 foreign-to-domestic share, with close to $1 billion overseas.

Opening-weekend estimates for “Avengers: Infinity War” are about $200 million, give or take $20 million; “Black Panther” opened to $241.9 over the President’s Day holiday weekend. Here are the cases for “Black Panther” and for “Avengers: Infinity War;” as always, all box-office figures adjusted.

Marvel

Why “Black Panther” Could Gross More

“Black Panther” was a standalone social phenomenon backed by strong reviews and original elements that made it stand out earlier this year, with limited blockbuster competition. It’s hard to see what factors another “Avengers” title has that come close to duplicating its appeal.

At $700 million, it will effectively tie with the first “Avengers” (2012) as the biggest Marvel (or for that matter, comic-book universe) film when adjusting to 2018 ticket prices. It’s a very big number, indeed the biggest other than “Star Wars: The Force Awakens” in 2012.

Only once before — in 2015, with “Force Awakens” and “Jurassic World” — have two films released in the same year reached that total. Two in the first half of a year would be unprecedented.

As with other genres, the longer it’s been since the last hit, the bigger the boost for the next. It’s been 72 days since “Panther” was released — the shortest gap ever between major Marvel movies.

The first “Avengers” grossed $705 million; the second $491 million. Historically, when a third Marvel entry outgrosses its predecessors, it’s beating titles that fell in the $200 million-$400 million range. To achieve $500 million for the third installment would be terrific (it’s great for any film). To hit $700 million would be historic.

We have a recent precedent of an ensemble title that followed a big comic-book success. “Wonder Woman” late last summer surprised the industry as a female superhero film grossing over $400 million. “Justice League” followed five months later with all major D.C. Comics characters, including Wonder Woman, and grossed around $230 million. The momentum did not carry forward.

Marvel Studios

Why “Infinity War” Could Gross More

“Black Panther” changed everything. Yes, they have been on steroids for years (nine films over $400 million so far), but with “Panther” approaching $700 million it proved the brand’s power is even more vital than its fans might have expected. The two “Avengers” titles and “Panther” are three of the five biggest Marvel titles ever, and the new “Avengers” title could be primed for equal success.

“Panther” also added a lot of viewers who were generally less interested in Marvel films. Unlike some studios, Disney doesn’t release racial/ethnic demographics, but a 2015 study of Facebook Marvel fan sites showed 11 percent of its members were African-American and 19 percent were Latino. According to studies outside Disney, “Black Panther” showed opening-weekend audiences as 35 percent African American, 17 percent Latino.”Panther” clearly shows Marvel’s appeal is universal, but that title (not unexpectedly) thrived with black moviegoers (who normally are 14 percent of ticket buyers). In addition to the Black Panther, “Infinity” features most Marvel characters (Sony’s Spider-Man, but not Fox’s X-Men or Deadpool). Is the carryover interest worth $100 million-$200 million to “Infinity”? It will need to happen to achieve parity.

“Avengers: Infinity War” starts the “summer” movie season in the last weekend of April — one weekend before the May date owned by Marvel since “Spider-Man 3” in 2007. That extra week of breathing room is great strategy. The mid-February release of “Black Panther” had the luxury of limited competition (it grossed five times as much as any other 2018 release, an incredible dominance).It will be May soon, and big films will open, but in its first three weeks “Avengers” faces only Melissa McCarthy’s “Life of the Party” as a would-be breakout hit. (Marvel’s own “Deadpool 2” and Disney’s own “Solo: A Star Wars Story” come up May 18 and May 24, taking some of the wind out of the sails.)

With a $200 million opening weekend, and $250 million or more in the first week, “Avengers” could reach $500 million after three weeks, just as summer is about to begin. A great initial response means it could soar much higher.

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