Trade unionist Zwelinzima Vavi is optimistic that his suspension as Cosatu general secretary will be lifted.
He was speaking outside the High Court in Johannesburg, which he and three Cosatu affiliates have approached in a bid to get the suspension lifted.
Cosatu opposes the action. Judge Phineas Mojapelo reserved judgment on Friday, after a day dominated by argument over whether Vavi's suspension was constitutional and whether the matter ought to be heard by the Commission for Conciliation, Mediation and Arbitration or the labour court.
Irvin Jim, general secretary of metalworkers union Numsa, was also confident.
"We are not saying we are going to win [but] ... we're very happy with the presentation," Jim told a small group of sympathisers during the lunch break.
Vavi was suspended after having sex with an employee in the union's offices.
Vavi said minutes of the August 14 executive meeting showed there was no seconder to the motion that he be suspended and no vote was taken, as required by Cosatu's constitution.
Vavi told the crowd: "The issue is there was no voting, full stop. We have a very good story to tell inside the court."