The fourth of six programmes that relive great sporting rivalries.

Sport collided with politics in 1974 in one of the greatest rugby clashes ever seen - the British Lions playing the Springboks in a tour of South Africa, a country then gripped by apartheid. The Lion's tour was opposed in Britain by politicians and activists.

Here, team members, including Willie John McBride, Gareth Edwards and JJ Williams, explain why they risked their reputations, and even their jobs, to breach an international embargo and take on the Springboks, a team unbeaten in 18 international matches.

Other contributors include: Steve Tshwete, at the time imprisoned on Robben Island and now South Africa's Sports Minister, and former Observer editor Donald Trelford, whose paper led a protest against the tour. Home cine footage recalls the team's progress.