In a letter to WRU member clubs, Gerald Davies said he made his decision not to stand for re-election to the board "with considerable sadness".
'On and off the field I hope I have demonstrated my passion and commitment to the game at all levels and I have endeavoured at all times to bring my lifetimes experience and knowledge to help contribute to the well-being of the game and all those who are involved in it throughout Wales as well as on the International stage.
I have always believed and stated that as rugby changes so its organisation must also change anD develop for the common good of all.
I do not wish to sever my ties completely with rugby and will constantly look for opportunities to encourage and support the game that is so dear to my heart.
I will watch with interest how the WRU meets the many challenges ahead."
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There is likely to be a good deal of cloud around today, thickest in the southeast, where outbreaks of rain are possible at times.
A dry night with clear spells for most, especially towards the north where it will become rather chilly with some mist patches possible.
Wales head coach Warren Gatland says some players suffered a few bumps and bruises during their clash against Ireland.