Anticipation is a key factor in the achievement of motor goals in striking sports. It involves perceptual cognitive skills, such as the ability to gather relevant visual information. However, anticipation and gaze behavior have never been investigated in a real-game setting. This setting implied increasing of fatigue and research of maintaining of performance. The aim of this study was to evaluate the effects of physical fatigue on anticipation and gaze behavior during a badminton game. Six international-level badminton players played two sets while wearing eye-tracking glasses: one before and one after a fatiguing task. To evaluate anticipation behavior with acute physical fatigue, we measured reaction time and split-step delay. To evaluate gaze behavior with acute physical fatigue, we measured the numbers and durations of fixations for each exchange and for ten areas of interest. Reaction times and split-step delays were shorter with fatigue. Fatiguing physical exercise led to fewer fixations per exchange and more fixations on one area of interest: empty area after participant's stroke. Fatiguing physical exercise had no effect on gaze durations per exchange or for any area of interest. This is the first study to use a mobile eye-tracking system to capture gaze behavior during a real badminton game in expert players: the results showed that anticipation and gaze behavior were adapted in acute physical fatigue in order to maintain performance.