In recent years, a robust sole arbitrator clause has been adopted by several international arbitration institutions such as ICC Arbitration Court and SIAC, which stipulates the application of a sole arbitrator tribunal against parties’ agreement to the contrary, on the condition that this clause is part of the arbitration rules that the parties have accepted. Questions ensue in the arbitration field, mainly focusing on whether the sole arbitrator tribunal is up to the same standard of fairness as traditional three arbitrator tribunal, and whether overriding parties’ agreement to the contrary defies the party autonomy principle. Analyzing from the perspective of the Expedited Arbitration’s value orientation of leaning towards party autonomy and prioritizing efficiency, this paper finds that the robust clause is striking a balance between efficiency and fairness, and upholding the principle of party autonomy.