Rugby's most most-capped player and former Wallaby captain George Gregan will join the Board of the Australian Rugby Union.

Gregan, 38, capped an international record 139 times for the Wallabies up to his retirement in 2007, is to replace Wallaby forward Mark Connors, who has served as the Rugby Union Players' Association's nominee, the ARU said.

"The RUPA Board has spent considerable time discussing the best past player to be nominated for this position on the Board steering the game and we were unanimous that George was the most credentialed and experienced candidate," RUPA chief executive Greg Harris said.

Gregan joins three other former Wallabies on the ARU Board - the 1999 World Cup-winning captain John Eales, Michael Hawker and Brett Robinson