At its most concrete, the replay is technology’s attempt to remove human error from an inherently human enterprise. Hawk-Eye and similar systems have reshaped the sport’s relationship with certainty. Where once a line judge’s raised finger was final and irrevocable, now pixels, algorithms, and frozen frames promise a definitive answer. This promise is seductive: it aligns with modern faith in data and the ideal of fairness. Replays guard against injustice—overturned calls correct outcomes, preserve rankings, and protect the livelihoods of players whose careers hang on a few crucial points. Yet the introduction of replay technology also complicates tennis’s phenomenology. The immediacy of a stadium gasp, the collective breathing in a tense rally, and the ritual of protest are altered when the final arbiter is a silent server of cameras. Spectators no longer share only in the raw unpredictability of human judgment; they now witness an interplay between perception and simulated infallibility.