Jon Bernthal often plays the tough guy. But when he got the script for Warner Bros.’ King Richard, about Richard Williams and his quest to make his daughters Serena and Venus the best tennis players in the world, Bernthal knew he wanted to be a part of it. Bernthal fought hard to play Rick Macci, the legendary tennis coach of the Williams sisters, and came to appreciate Macci’s sincere love for the game and the Williams family, as well as Macci’s coaching method.

Bernthal and Macci spoke to THR about their collaboration to accurately portray Macci on the big screen, how Bernthal learned to play tennis for the role and what advice Macci gave Bernthal to get inside his mind.

Rick, what was your reaction to hearing that this movie was in the works?

RICK MACCI Back in the day, Richard always would say some wild things. Early on, before [Venus and Serena] were even anything, he always told me not only how good they would become, but that they were probably going to do a movie about the kids someday. He even said, “Someday, Rick, they’re going to make a movie about me.” I think telling this story through the eyes of Richard, and exactly how this played out … people are blown away. You can’t make this stuff up. He and I were on a mission, and I love the guy to death.

Jon, what drew you to the project and to the role of Rick?

JON BERNTHAL So much. I fought for this. They didn’t see me for it initially. And I really, really wanted to do it. What’s so beautiful about telling this story is that everybody has some knowledge of [them] — like you said, they’re perhaps the biggest sports icons alive right now. I think it’s so much better to not have it be this highlight film of Grand Slams and Wimbledon. The palpability of how impossible this dream was is really highlighted by telling the story at this time. The script blew me away. I’m an ex-athlete, I’m raising young athletes, and I thought that this story really explored the full spectrum of youth sports and how toxic it can be, all the way to how sublimely beautiful it can be. As far as Rick goes, some of the coaches in my life have had such an unbelievable impact on who I am as a man, as an artist, as a father, as a husband. So much of the time, coaches in movies are portrayed as these taskmasters or complete hard-asses. The thing that I was just really taken with about the way Rick was portrayed in the script, and then everything that I’ve heard about him, it’s just that he’s got this pure, unadulterated love for the game. And that he coaches with joy and with passion. You know, Serena told me that her time playing for you, Rick, was the most fun time in her life. It’s the first thing she said.

MACCI Trust me, she’s a character.

BERNTHAL But so are you! She said, “He made everything fun, everything was a game, everything was a contest.” I know [from] raising my own kids who are athletes themselves, keeping it fun, keeping it enjoyable, is so important, and especially when you’re dealing with the level that you are when it’s such high pressure. I love that there’s such an unbelievable lesson there. In studying you and reading your books and looking at your interviews, I love the way that everything is a game. It’s so tenacious, it’s so fun, you do it with so much love and passion. I also really felt that at the end of the day, you just really are a part of that family. You love those young women like they were your own.

Rick, how much input did you have in who was going to portray you?

MACCI There were so many people who told me they wanted to play me — it sounds weird. But Jon ended up the leader in the clubhouse. They told me when I went out to California that he wasn’t first on their list, but like anything in life, sometimes when you have to fight harder, you end up winning the thing.

How did you guys collaborate?

MACCI Right off the bat, we talked a handful of times on the phone. I have a lot of stuff all over the internet, videos, and there’s some books. Jon said it best: I think talking to people, the many people that I coached … you get the feel of how I was. I’ve got to mention Richard. This guy, even when I went to Compton, he turned on a [camera]. I thought I was in a deposition with this guy. This guy grilled me. He videotaped everything. You couldn’t ask for a better treasure trove of what happened. [The] only thing that was different, Jon had this, like, shrubbery on his face. I had this tight little piece of AstroTurf that took me 30 years to grow. So other than the mustache, I love the guy. You hit it out of the park.

BERNTHAL It was such a joy for me to channel you, man. I believe in the way that you conduct your life. It was a joy for me to play such a joyous person. I played sports my whole life. I did not know much about tennis when this thing started. But I am a firm believer that if you’re going to do a sports movie, you’ve got to get the sport right. I find it enormously disrespectful when films don’t do that. I was enormously grateful to the producers to give me the infrastructure to really learn the game of tennis. I trained at an academy out here in Ojai for three hours a day. I lost 30 pounds. I would learn the game of tennis, but then I also got to learn how to coach. I worked with a top 50 junior nationals player named Kamea Medora, who was awesome, and I trained her in character. To be able to do those drills and be able to coach in character, I felt that then stepping in, I was in a great place. The other thing is, Rick — I mean, besides the unbelievable sexiness and beauty of that mustache, and your overall thing you’ve got going on — you have one of the most unique voices and dialects and speech patterns of anyone I’ve ever heard. That was one thing I really wanted to get right … but the thing that I felt like I was most interested in was your heart. Your heart, loving these two young women, loving this family, wanting to be a part of this mission. And [having production] shut down for six months [during the pandemic] gave me six more months to keep on preparing, keep on playing, keep on training.

What’s one piece of advice Rick gave you?

BERNTHAL That you can be tough, and you can be tenacious, and you can be an animal, and you can do it with a smile. A lot of people have talked to me about how this is a different kind of role for me, that I’m usually playing these tough guys. I think Rick Macci’s enormously tough! He’s just this unbelievably strong figure, and he does it with a pure, unadulterated love and passion.

MACCI This is why Jon won the sweepstakes, and he got to play me. I couldn’t have said that any better. See, the art of coaching, there’s not a wrong way or right way, there’s a better way. There’s an art to this thing. I’ve been on the court since age 22, probably [longer] than anybody in the world. And then you’ve got to deal with the parents. … People say, “Why did I do this?” Why did I take the chance? To me, there was no chance. I believed in myself. I knew what I could do. But I saw something in these two little girls that I haven’t seen my whole life. I saw a rage inside these two little kids to get to the ball. And they transcend the sport. There wasn’t any risk. The only way I lose is if I can’t deal with Richard, but I could deal with Richard. And he knew that I was all in. When you get that power, and you have the goods, and Venus and Serena, the rest is history.

BERNTHAL One of the things that Rick was getting at that I found really interesting is, these are two men who are very used to doing things their way. What I really love is to play interesting, complicated and fascinating characters and put them in very interesting, fascinating and complicated situations. So there is this art about, I’m here to do my job, to train these kids, to make them the best that they can be. And now you’ve got to deal with this whole other thing, which is Richard Williams, and I think a lot lesser men would have sort of succumbed to that.

MACCI You can see in the movie how stubborn Richard was. One quick story: They go from Compton, from that house you see, to that five-star resort-like house [in West Palm Beach, Florida] that’s like the Taj Mahal, and about 10 days into it, he calls me up at 11 o’clock at night. And Richard goes, “Hey, Rick, you got to get over here. Someone’s trying to kill me.” I go, “Richard, wait a minute. If I come over, they’re going to kill me, too.” He started laughing. I go, “Richard, it’s probably security. Don’t worry about it.” He goes, “Rick, you’ve got to get over here.” So I said, “OK, Richard, I’ll get dressed. I’ll be over in 15 minutes.” He goes, “Rick, don’t worry about it. I’m just kidding. I just wanted to see how much you cared about our family.” Like Jon said, it takes a certain guy to take a punch, and to be able to just let it roll off your back. And honestly, the best vacation I ever had in my life was in Compton, California, believe it or not.

Interview edited for length and clarity.

This story first appeared in a January stand-alone issue of The Hollywood Reporter magazine. To receive the magazine, click here to subscribe.