The boxing trainer Emanuel Steward, who has died at the age of 68 from complications following surgery for the stomach disorder of diverticulosis, was revered throughout the sport not only as probably its greatest teacher of the modern era, but also as a supreme communicator. Few have analysed fighters and described their strengths and weaknesses with such clarity and simplicity.
He was engaging company, charming and mischievous, with a readily approachable manner that made him a godsend for print and broadcasting journalists for more than 30 years as he coached more than 40 fighters to world titles. A natural performer for the television camera, from 2001 onwards he was employed by the American cable network HBO as a commentator.
But Steward will be best remembered as a trainer. He worked closely with the world heavyweight champions Lennox Lewis and Wladimir Klitschko, helping both men to eradicate flaws in their technique to become the best of their time. They had complete trust and respect for Steward's coaching acumen, and also loved his worldly wise manner and warm friendship.
While Steward's name became known internationally, he maintained his base in Detroit. He was born in Bottom Creek, West Virginia, where his father was a coalminer and his mother a seamstress. They divorced while Emanuel was a boy, and he moved with his mother to Detroit. There he learned to box in the celebrated Brewster Recreation Centre, where Joe Louis, the great heavyweight champion of the 1930s and 40s, had learned his trade.
Steward was a talented amateur fighter, good enough to win the bantamweight National Golden Gloves title of 1963. But rather than turning professional, he worked as an electrician before finding that coaching was the role that suited him best, starting with his half-brother, James. Based in the Kronk gym in Detroit, named after a prominent local Polish-American politician in a rough, run-down neighbourhood, Steward produced a conveyor belt of champions, most notable among them Thomas "the Hitman" Hearns.
A visit to Kronk was an amazing experience. A small community centre owned by the city, it stood with its windows protected by metal grills amid burnt-out houses and cars in an area torn apart by gang wars and social deprivation. Yet, more often than not, a gleaming Rolls-Royce convertible would be standing untouched outside, indicating that "Manny" was within, working with the stable of fighters who, to him, were as close as family.
On the ground floor, kids played table tennis and listened to music. But it was downstairs, in the stiflingly hot basement, that legendary feats were planned. On the walls, photographs and fight progammes bore witness to the Kronk's achievements, while fighters pummelled speedballs and the heavy bags that hung from the low ceiling. It was in the single ring though, illuminated only dimly, that fighters honed their skills under Steward's watchful eye.
He started there part-time in 1971, and left the electric company Detroit Edison to work full-time as a trainer the following year. Champions such as Milton McCrory and Mike McCallum survived fearsome gym wars and became great professionals in the process. But it was Hearns who stood out as the true Kronk hero.
He had been a talented amateur, a light puncher known primarily for his gangling physique. With Steward, he was transformed into "the Motorcity Cobra", an awesome puncher who went on to be a world champion renowned for his rivalry with Sugar Ray Leonard, Roberto Duran and Marvin Hagler. Hearns and Steward remained close friends after Hearns's retirement in 2006 and, as Steward's condition worsened in recent weeks, Hearns led prayer vigils.
In addition to Lewis, the British fighters who worked with Steward included the WBO world featherweight champion Naseem Hamed and the Londoner Dennis Andries, who lost a WBC light heavyweight title fight to Hearns in 1987, but then based himself in the Kronk gym, working with Steward and winning the title back two years later against the American Tony Willis.
In 2006 the Kronk gym was closed by the city authorities, and Steward moved his operation a few blocks away. His marriage to Marie Steele ended in divorce, and he is survived by his partner, Anita Ruiz, who is also executive director of the Kronk Gym Foundation, two daughters and two sisters.