Ninety minutes is the preferred running time for most new plays these days. But it’s just not enough for what Marco Ramirez attempts with “The Royale,” now being given its world premiere at the Kirk Douglas Theater in Culver City. Director Daniel Aukin stages quite a show — technically and choreographically, it’s like a musical without songs — but this bioplay of the first African-American world heavyweight boxing champion pins too much of its drama on one underwritten character. And it’s not Jack Johnson.

For his dramatic purposes, Ramirez calls him Jay Jackson (David St. Louis). In his 1967 play, “The Great White Hope,” Howard Sackler used the name Jack Jefferson, letting us know that his drama was not strictly bound by the facts. Ramirez’s take is much more freewheeling. Although the title bout is staged, we never actually see the actor playing the Canadian boxer Tommy Burns, referred to here as Bernard Bixby. Instead, Ramirez has Jay’s sister Nina (Diarra Oni Kilpatrick) be a sort of stand-in for that white fighter. It’s a concept that takes some explaining, although due to the considerable talents of Ramirez and Aukin it makes total sense as staged.

Nina is the symbol of why Jay is fighting, he says. Nina is also supposed to be the reason he should lose the fight, she says. That is a lot of weight to put on any character, especially one who is introduced to us only a couple of scenes earlier. Jay recalls perfume ads that featured female models who did not resemble his sister, who has suffered serious burns trying to straighten her hair.

“‘Cause she ain’t never seen no posters looked like her, he cries.

But Nina’s son has already been beaten up in a fight, and she fears what bigots all over the country will do when the world heavyweight boxing champion is no longer a white man.

“Look at the dogs you’re about to unleash. And don’t say I didn’t warn you,” she cries with equal force.

Remember that these speeches are delivered as the title bout takes place. Aukin has ingeniously prepared us for this bit of legit legerdemain by staging a previous fight in which the two boxers face not each other but the audience, as if it were readers theater without the scripts in hand and punches not so much thrown as stomped on the boards, and we see the result of those blows as heads swerve and bodies fall. It’s great staging accompanied by a whole battery of dazzling lighting and sound effects by designers Lap Chi Chu and Ryan Rumery. Rather than being a fight coordinator, Ameenah Kaplan is aptly credit for “movement and rhythm.” The movies show us what happens to a fighter’s body, Ramirez succeeds in showing us what happens to a fighter’s brain.

The same derring-do takes place in that second bout, with Jay and Nina on stage. But heretofore, Nina is only a speech about her little boy and her fears for the future. Even though Kilpatrick nearly matches the ferocity of St. Louis’ performance, she’s a symbol, not a character.

And a cliche at that. How many dramatic works pit the man with a dream against the woman with a family? As played by St. Louis and written by Ramirez, Jay is simply too focused and driven in his dream for Nina ever to be a real threat. She just needs to be quickly pushed out of the way for history to happen.

The Royale

(Kirk Douglas Theater, Culver City; 131 seats, $50 top)

A Center Theater Group presentation of a play in one act by Marco Ramirez. Directed by Daniel Aukin. Set and costumes, Andrew Boyce; lighting, Lap Chi Chu; original music and sound, Ryan Rumery; movement and rhythm, Ameenah Kaplan. Opened and reviewed May 5, 2013. Running time: 1 HOUR, 30 MIN.

With: Robert Gossett, Diarra Oni Kilpatrick, David St. Louis, Keith Szarabajka, Desean Terry.