http://www.calgarysun.com/sports/gol.../14086356.html
http://aga.bluegolf.com/bluegolf/aga.../scorecard.htm
A good buddy of mine fired a 25 on the back 9 at Carnmoney in an Alberta Tour event.
As the article says, Corey Pavin had shot a 26. Other then that, at least through googling searching, no other record of someone shooting that low on a front or back 9 at least in a professional tournament.
Also, guess he left another eagle putt an inch short on the 12th hole.