For the first time in decades, two actors are sharing the lead role in a Guthrie Theater production. Artistic Director Joe Haj cast Stephen Yoakam and Nathaniel Fuller — both highly esteemed local veterans — to alternate in the lead role of “King Lear” in a production that is now in previews and opens Friday.

This will be Haj’s first homegrown staging of Shakespeare at the Guthrie. Haj did not initially intend to cast both men.

“When Yoak and Nat came in [to audition] for Lear, I spent 20 minutes to half an hour with each of them and I was left with this quandary,” he said Haj. “They’re both gigantic actors and I was going back and forth between them. Finally, I said to the staff, ‘What would it mean in terms of rehearsals, previews, logistics and all that if we cast both of them?’ They said the challenges were not insurmountable.”

The last time two actors alternated in a lead role at the Guthrie was more than two decades ago when Fuller and Richard Ooms shared Scrooge in “A Christmas Carol.”

Haj said it’s crucial that the men work as collaborators, not frenemies: “If they feel that it’s a competition — that they’re arm-wrestling to be the best Lear — then that could get ugly. But they’ve both been a dream and it’s moving to watch these two giants, who’ve done over 150 productions between them, care so much for each other. “

Fuller and Yoakam have performed together in 40-plus Guthrie productions, the last being “The Crucible.” They sat down before a rehearsal to talk about sharing a role that last was performed at the Guthrie a decade ago by the great British actor Ian McKellen.

Q: The role is operatic in its heft. Has it been on your respective bucket lists?

Fuller: For just about all my career, I hoped that I might get a crack at it. I didn’t get to do Hamlet. I didn’t get to do Richard III.

Yoakam: I remember seeing Len Cariou do it when I was in college. [Cariou played Lear at the Guthrie in 1974.] If you’re a jazz musician and you see Dizzy Gillespie or Miles Davis play, you go, “Someday I’m gonna be able to play there.” 

Q: How does a collaboration like this actually work?

Fuller: We get together for a conference with the director. I’ll do a scene and Yoak would come over and say, “I was wondering about doing this or incorporating that.”

Yoakam: So we’re stealing from each other. There’ll be a similar arc but the chemistry and rhythms will be different.

Fuller: There’ll be different timings, yes, but I feel like we’re in fundamental agreement about the overall values of the play. It’s great to sit outside sometimes and watch a scene happen. We’re actually never both onstage in the rehearsal process. If we’re together it’s because one of us got up from our seats to go over and join the conversation [with Haj]. 

Q: Tell us more about the working process.

Fuller: We were cast in October. We met with Joe for a couple of sessions, going through the script before the year was out.

Yoakam: We talked process and some textual ideas that maybe we wanted to restore or leave out because they don’t seem to add to the thrust of the play. Because Joe is an actor and was in the repertory company, he’s a true collaborator. [Haj was a Guthrie company member in 1989-91.] He knows that it’s not gonna get made the way he wants it to be made unless there’s true collaboration in the room.

Fuller: He listens but he’s not locked in.

Yoakam: He’s got strong ideas about the shape and how strong the motor needs to be when it’s advancing, and where it needs to lay off.

Fuller: In this production, you won’t be struck by special effects. There are a few. But it’s about the text, about being direct, true and open.

Yoakam: I love the way he thinks outside the box by asking two guys to share the role and by also, in his first full season as artistic director, saying, “Hey, I’m gonna do Lear.” 

Q: Did the size of the role scare you?

Fuller: We both researched and read all about the epicness of Lear, the unactability of the role and the unproduceability of the show. The funny thing is that it has surpassed “Hamlet” as the most produced Shakespeare.

Yoakam: All that reading turns out to be of no help.

Fuller: We just decided we had to throw those things out. What it boils down to is basic acting: figuring out the story, making choices, getting into the emotions. Of course, this being Shakespeare, there are certain vocal demands that we have to surmount. 

Q: Lear has been essayed by some great actors.

Fuller: If I think about having to measure up to [John] Gielgud or [Laurence] Olivier or McKellen or [Paul] Scofield, I’m dead. I have to go in every day and do my work. I have to take each problem as it arises and solve it.

Yoakam: It’s interesting, having remembered Cariou’s Lear, and seeing Ruth Maleczech do an all-female Lear with Mabou Mines, and McKellen a few years ago. These are great touchstones but they just add to the texture or fabric of the experience for me. I might like a gesture that they did or something else, but this is about acting in the moment, reacting to what we see onstage.

Fuller: You turn around and see this Gloucester or Goneril and it’s different. We’re developing a relationship on our feet here, reacting to what’s in front of us. 

Q: Lear is a king who loses power. At its most elemental, what is the story about?

Yoakam: It’s a story about love and a declension of health. The loss of love is the biggest poison for him.

Fuller: It’s also about the loss of identity. Throughout his whole life, Lear has been very sure of who he was and what his place was in society. He got what he wanted. People did what he said. He’s able to dominate his children. If you’re that locked into that, when that gets stripped away and you first become confused, then you become more confused about why people are reacting to you so differently. By the time you go out into this storm, who are you?

Q: He loses his memory and goes mad —

Yoakam: I’m not sure we’d put a clinical identifier in terms of cognitive loss and all that.

Fuller: Lear says what he says and does what he does in much of the play because it’s clear in his own mind. In fact, some of the things that you see him doing with the mock trial and some of the scenarios, it’s almost what you might expect from a person in therapy getting in touch with their feelings. To the outsider, it looks totally crazy. But he’s working on a problem of trying to either get justice or revenge, or recover power in his own mind when he has no physical means of doing it. He’s mentally reaching.

Yoakam: Most of the time he’s in the room saying: “There’s a problem in front of me that I need to solve.”

Fuller: We’re not trying to do a lot of gestures of craziness or a tone that this guy’s out of his head. It’s all absolutely clear to him. 

Q: What parts of the play suggest the world today?

Yoakam: It starts with a dizzying sense of forward moment, a blizzard of activity. The entire court is going, “What the hell is going on?” as a result of executive decisions that come seemingly out of nowhere. It puts everyone off their game. Their molecules are scrambled.

Fuller: When we say a line that speaks to the moment, Joe says, “We’re not doing anything to signal that. The play speaks for itself.”

Yoakam: A line that pops up for me is when Gloucester says, “As flies to wanton boys are we to the gods —

Fuller: “They kill us for their sport.”

Yoakam: Lear says, “Get thee glass eyes and like a scurvy politician seem to see the things thou dost not.” And: “The usurer hangs the cozener.”

Fuller: We changed it: “The great thief hangs the little thief.”