Both are seasoned administrators and will add credibility as the board almost immediately considers a review of this year's performance.
Joy is general manager for the Dunedin base of the 2015 Fifa Under-20 World Cup, and Rickerby has been involved in senior cricket and football administration.
There will be a measure of deja vu in Rickerby's appointment, since he held the same post in 2008 when Wilson James resigned his general manager job to take over finance.
However, retirements by chairman Phil Cunningham, manager John Mathias, Darren Burden and Dave Lamont leave Kevin Kaiser, Marcel Rodeka and Gerry Sannum to soldier on. Invercargill-based Ken Creswell is reportedly still involved.
In the season's final match against Wanderers in Invercargill tomorrow, Southern United needs a big effort to evade the wooden spoon.
In the first round, Southern beat Wanderers 2-1 in a dramatic match in which Andrew Ridden, and Henrique Viana scored, but the team went down to 10 men for a nail-biting last half-hour.
Southern coach Luiz Uehara has talked at length of long-term targets, including ''match perception'' and ''awareness of strategy'', but his performance as coach this season will probably be judged by evading that bottom slot.
He has experienced goalkeeper Jefferson Potrich back between the sticks, and as near a full squad as he has had for some while. The only recent absentee is midfielder Sam Mepham, who is suspended.
However, having more players available in a way sets Uehara more problems, since he has rarely fielded a settled team, and his player selections have generated some opinionated debates among Southern supporters.
Wanderers coach Darren Bazely also has preached pure football to his youth team but, like Uehara, may consider a more direct approach using pace and penetration on Sunday.
The former Watford professional is preparing his side for the Under-20 World Cup, and in this final match realises just how important it is for morale not to finish bottom in the ASB Premiership.
Wanderers recently lost defender Brock Messenger and twins Tom and Stephan Trbuhovic, who have all returned to Australia.
Southern is two points ahead, with seven points from 13 games including two wins and a draw. Its goal difference is -33, after conceding 47 goals.
Wanderers presently sit bottom, with five points from one win and two draws in 13 matches, and a goal difference of -18.
A draw would suffice for Southern, but both teams are likely to go for the jugular in a winner-takes-all approach, which should entertain Invercargill's footballing public.
At the other end of the table, defending champion Waitakere has to win to make the top four playoffs. Opponent Canterbury can sneak in with a draw in Whenuapai.
Southern United's youth side travels to Manawatu tomorrow.
Southern v Wanderers: Invercargill, tomorrow, 2pm
Southern United: Jefferson Potrich, David Hayman, Peter Overmire, Campbell Attwood, Henry Flood, Nick Hindson, Morgan Day, Andrew Ridden, Taylor McCormack, Peter Rae, Campbell Higgins, Jacob Schneider, Logan Wrightwebb, Regan Coldicott, Dan Morris.
Wanderers: Zac Speedy, Deklan Wynne, Adam Mitchell, Reilly O'Meagher, Andre De Jong, Nick Sugden, Scott Doney, Ben Thomas, Stu Holthusen, Cameron Hogg, Elijah Neblett, Nick Forrester, Finn Cochrane, Daniel Ridgley, Michael De Heijer, Nathan Buswell.
