Matt Giteau and Drew Mitchell will have one final chance to play for silverware together, after Toulon survived a thrilling Top 14 semi-final against La Rochelle.
A last-gasp drop goal handed Toulon the win, 18-15, with regular season leaders La Rochelle, including Aussies Brock James and Zack Holmes, knocked out.
Giteau is headed to Japanese Top League side Suntory for the 2017-18 season, while long-time teammate and friend Mitchell is set to retire after this final.
Mitchell played on the wing for Toulon, in his second-last professional match, as Welsh fullback Leigh Halfpenny kicked five penalties to keep them in the tryless encounter.
James O'Connor was at inside centre and found himself in the middle of one of the game-defining moments, on the end of a dangerous tackle that put La Rochelle a man down.
O'Connor was replaced by Giteau after that, with the latter playing 27 minutes of the sudden-death match-up after being a surprise inclusion in the team.
Liam Gill was at openside flanker, playing 73 minutes for Toulon, continuing his strong form.
Next weekend's title decider could be the 24-year-old's final Toulon match as well, with French media reports suggesting Toulon owner Mourad Boudjellal would consider selling the former Wallabies backrower.
A move to Lyon could be on the cards for the former Queensland Red, where he would link up with fellow Reds ex-pats Mike Harris and Curtis Browning.
Toulon will take on Clermont after they defeated Dan Carter's Racing 92 37-31 in the other semi-final.
Despite being reduced to 14 men after Flip van der Merwe was sent off after 41 minutes for a dangerous tackle, Clermont held on to avenge their
elimination in last year's semi-finals by the Parisians.
Four tries laid the groundwork for victory with Camille Lopez (27, 47) touching down twice with Damian Penaud (18) and Fritz Lee (64) also going over.
Racing scored three late tries with a Chris Masoe double on 70 and 77 minutes followed by Ben Tameifuna on 81.
Will Genia's Stade Francais will not feature in the 2017-18 Champions Cup, with Northampton defeating the Challenge Cup champions 23-22.
Genia will return to Australia next week, ahead of the Wallabies' June Series.
Top 14 semi-finals
La Rochelle 15
Pens: James 4
Pens: Halfpenny 5
Champions Cup playoff
Tries: Foden, Tuala
Cons: Mallinder 2
Pens: Mallinder 3
Stade Francais 22
Tries: Vuidarvuwalu, Sinzelle, Camara
Cons: Plisson 2