Welsh rugby legend JPR Williams has warned that the modern game must "wake up" to the increasing problem of career-ending injuries.
The 1970s Wales and British Lion full-back is a consultant surgeon researching how to prevent rugby injuries in play and in training.
"I was never averse to putting in big tackles," he said. "But the modern game has gone a big step further".
He spoke ahead of a University of Glamorgan conference on rugby injuries.
The event will see four new academic research scholarships announced, including a partnership between JPR Williams and the university into rugby injuries and how they can be prevented.
Research will include treatments for brain, spine shoulder and joint injuries, as well as how oxygen chambers can help players train and recover.
Williams, aged 61, is one of the legends of the Welsh "golden era" of the 1970s, when the team captured three Grand Slams.
He won 55 caps for Wales between 1969 and 1981, and stopped playing local rugby only seven years ago.
But he said the modern game was "more physical" than in his time.
He said: "Players train more, they are bigger, stronger and tackle harder.
"With the tension between clubs, regions and countries, today's players play more often and at higher intensity than ever before.
"They're being subjected to a vast increase in training by the fitness coaches, to the extent that many injuries now sustained in training are from overuse.
"These injuries are often career-ending. It's time for the game to wake up and take this seriously."