In 1970, in a dispute about training, Watkins left Newport to join rival club Cardiff.
Played at the Cardiff Arms Park, it was Scotland's only defeat of the season and would be the key game in Wales winning the championship that year.
It was the final game of the tournament and Wales were trailing by 8 points to a team they had beaten only once in the last eight encounters.
[3] Keith Bradshaw had dragged Wales back into the game with two penalty goals when Watkins intercepted a French three quarter movement on his own 25 yard line.
He raced 75 yards down the right touch line to score a memorable try that not only gave Wales the match but also the championship.