In a city that operates as a revolving and ruthless casting couch for aspiring stars, the Wild Card boxing gym in Hollywood, Los Angeles, offers a puncher’s chance for fighters to shine. Freddie Roach, the gym’s owner and trainer, surveys the first fighters through the door from the front desk. The sun has just risen, bringing some warmth to an uncharacteristically cold Californian morning. Roach’s clientele has always been eclectic. He began the morning training Puerto Rican legend Miguel Cotto at 5am sharp, will soon be making plans with Manny Pacquiao and will spend the afternoon helping a 12-year-old girl who wants to learn the sport.

Everybody who walks into the gym is greeted warmly by Roach and his elderly mother Barbara at the door. You pay your five bucks and get ready to train hard. Whether you are a portly accountant aimlessly windmilling at the heavy bag or a hard-nosed prospect, you will be treated with the same cordial respect.

Aged 56, the man who was known as “the choirboy” when he fought in the ring, remains blissfully enthusiastic about teaching his sport now he is largely outside the ropes. “I get up every morning, not because I have to, but because I’m so grateful for what I do with my fighters. I live just down the road and I work 12 hours a day. I’m in early and I finish late. My mother lives just beside me, which is great. At the end of the day, I go back see her three dogs. One always waits for me so it’s become a favourite. I rest and start again. I treat everyone the same, whether that’s Manny or a young girl trying the sport. In the gym, it’s a question of getting the right mix of personalities and I believe we have that just right.”

Wild Card has become a tourist attraction of sorts in Los Angeles. The gym is situated in a lot between a pawn shop and a selection of Mexican restaurants, and fight fans come from all over the world for a chance to see Roach at work. Roach patiently spends time talking to visitors and takes an interest in where they are from. “Where is that accent from Jonathan?” he asks me. “Ah Belfast? I’ve never been there, although I’d love to, I trained Stevie Collins [the two-time world champion from Ireland] and I brought Mom over to Cork once when he fought. She loved it.” “I bought 300 bucks’ worth of Irish lace as a keepsake and didn’t know what to do with it,” adds Barbara. Roach taps his fingers to a song. “Van Morrison, he’s one of your Belfast boys as well, isn’t he?”

Roach’s long-time manager and multitasker extraordinaire Marie finds us a small office to sit in and chat away from the tumult in the upstairs gym. Beneath Miguel Cotto’s embossed training gloves, Roach talks about his start at the Wild Card. “I learnt from a legendary trainer, Eddie Futch, and then eventually I got to start this place. It wasn’t easy at the start. It never really is. I remember I used to come in early, clean the toilets, scrub the walls, everything, because I always wanted it to be respectable. This is around 20 years ago and then this man came in and asked could he train. It was Muhammad Ali. He stayed four hours, trained, signed autographs and showed us these magic tricks. I remember him hitting the bag, wham, it was perfect even then. I said to him, Muhammad, we have something in common, when we are boxing, we don’t shake anymore, we’re in our comfort zone.”

Like Ali, Roach suffers from Parkinson’s after a punishing professional boxing career. His shakes have noticeably lessened recently, and he tells me that he feels little physical pain. “In the ring, that’s when I feel free. When I do the pads with a fighter, I know within one round whether this person can be a world champion or not. Somehow you just know. The first time Manny came into the gym, I didn’t really know him. But as soon as we started doing the pads, it was honestly like I had known him my whole life and that was it. We’ve been together ever since.”

Pacquiao and Roach have developed a close bond that has moved far beyond their telepathy on the pads or in the corner during fights. Roach swore never to get too close to a fighter after he enjoyed too many nights out partying with his first world champion, Virgil Hill, as a young man, but the mention of Pacquiao always makes Roach smile. “Like all great fighters, Manny has had to change as he’s got older. He’s a religious man now and he didn’t want to hurt his opponents like the past. He’s not quite as mean. But I’ll tell you this, he’s a better father, husband and a person than ever and that’s what is important in this life.”

Facebook Twitter Pinterest Manny Pacquiao trains with Freddie Roach in the Wild Card gym. Photograph: Michael Nelson/EPA

Roach’s client list of legendary fighters is lengthy. Oscar De La Hoya, Mike Tyson and Bernard Hopkins have all ducked under the Wild Card ropes and rattled his pads. Roach laughs at the mention of Tyson. “Do you know Mike Tyson has the best incredible memory you can imagine? He came here to the gym not so long ago, and he pointed out individuals who worked here and said: ‘You fired him, him and him.’ He told me why I’d fired them exactly, then started asking me why they were back. I said: ‘Mike, you know how it is.’ Then he said: ‘Give me a fucking job.’ I said: ‘Anytime you want Mike.’ Then he started asking why I didn’t have his picture on the wall like the others. So, if you look over there, there’s a small picture of him by the ring. He’s always fun, with the best incredible mind and memory.”

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Roach is famed for his ability not only as a technical teacher of fight craft, but for his emotional intelligence in reading a fighter’s psychological profile in the build-up to a bout. I ask him how he deals with a fighter who is nervous before going into the ring. “I have something like that right now with a fighter. He’s got ability, but sometimes his mind can get caught up. It’s my job to fill his mind with positive thoughts and make him understand that it’s going to be fine, that he has done everything possible before he steps through those ropes. I take it upon myself to be there in the lead up to the fight, to keep them calm as possible.”

In the city of stars, the gym is regularly visited by Hollywood luminaries including Mark Wahlberg, Sylvester Stallone and Christian Bale. “We actually had Stallone in the other week after Trump’s inauguration. He was in to collect a T-shirt from the gym. I was chatting to him, but I was busy tying Miguel [Cotto]’s gloves. I have to concentrate on what I’m there to do. I’m always at work, it never really stops.” Another long day in Los Angeles stretches ahead for Roach at the Wild Card. Whether you are a prospective world champion or a five-buck one-time trainer, this is one place in Hollywood you can guarantee an attentive audience.

• This article is from Behind the Lines

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