 In 1970 , Wales shared the Five Nations with France , and recorded a 6 – 6 draw against South Africa in Cardiff . The following year Wales recorded their first Five Nations Grand Slam since 1952 . Using only 16 players in four games , the 1971 side achieved their most notable win of the tournament in their victory over Scotland ; after a last minute try by Gerald Davies that reduced Scotland 's lead to 18 – 17 , <unk> John Taylor kicked a conversion from the <unk> described as " the greatest conversion since St Paul " to give Wales a 19 – 18 win . Wales contributed more players than any other team to the British and Irish Lions that toured New Zealand that year . Those Lions became the only to win a series over the All Blacks . 
