The family of a black boxer who was once called “the best in Europe” but was prevented from fighting for the British title because of the colour of his skin has demanded a formal apology.

Although Cuthbert Taylor, from Merthyr Tydfil, competed as a flyweight for Great Britain at the 1928 Olympics – the first black boxer to do so – his talents were never fully recognised because of the colour bar.

The bar, which ran from 1911 to 1948 and was presided over by the British Boxing Board of Control (BBBC), which continues to run the sport, said fighters had to have “two white parents” to compete for titles.

Born in 1909 to a father of Caribbean descent and white Welsh mother, Taylor was deemed “not white enough to be British” by the board.

A memorial for Taylor, who died in 1977, was unveiled on Saturday at the Court House in Merthyr Tydfil, where Taylor used to train, to mark Black History Month. A plaque states the boxer was “denied the chance to succeed because of the colour of his skin”.

Merthyr MP Gerald Jones also used the opportunity to call for an official apology. Jones led a debate in the Commons last year on historical discrimination in boxing and used it to underline the “remarkable talent” of Taylor. He told the Commons: “Due simply to the fact that his parents were of different ethnic backgrounds, Cuthbert Taylor would never have the recognition and success at professional level that his remarkable talent deserved.

“That was all because of a rule that left a stain on the history of one of our country’s most popular and traditional sports, one that has otherwise been known for bringing people from many different backgrounds and communities together.”

Raising the matter again last week in parliament, he said: “This blatantly racist, discriminatory and shameful policy prevented many people from achieving their potential and, unbelievably, the British Boxing Board of Control has yet to apologise.”

Jones has also asked the organisation to undertake work promoting the role non-white boxers played in the sport’s history. The BBBC had still not apologised or responded to requests for comment at the time of writing.

Alun Taylor, the boxer’s grandson, said he was “sickened to his stomach” by the board’s treatment of his grandfather. He added that the board’s attitude meant that he had advised his two grandchildren, who both box, to never mention their black roots or connection to Taylor.

Taylor, a bantam and lightweight boxer, had had more than 250 official bouts in his professional career, recording 151 wins, 22 draws and 69 defeats between 1928 and 1947.

Yet boxing historian Gareth Jones said Taylor’s career was likely to have been significantly more extensive than that and would have even involved fighting two 12-round bouts in the same day. “Cuthbert and his father Charlie fought in the boxing booths on travelling fairs. There they would have fought dozens of bouts against all comers of all weights and sizes,” he said.

In 1935, Taylor and American world champion lightweight Freddie Miller sold out Liverpool’s Anfield stadium in a charity fight to raise funds for the victims of the Gresford pit disaster, near Wrexham, which claimed the lives of 266 miners.