On-court position influences skilled tennis players' anticipation of shot outcome.

When anticipating future events like an opponent's stroke direction in tennis, players are assumed to rely on both kinematic and contextual cues such as an opponent's on-court position. However, knowledge of position dependency in shot-direction probabilities and experimental evidence of the effect of on-court position on action-outcome anticipation is missing. Here we show that shot-direction probabilities vary as a function of a hitting player's on-court position in professional tennis. Moreover, unlike novices, skilled players in particular relied on information about an opponent's position when anticipating forehand baseline shot direction in a video-based experiment. The position dependency in skilled players' prediction behavior was most evident when little information on an opponent's stroke kinematics was available. Findings suggest that skilled players consider the reliability of different information sources by weighting the available contextual and kinematic cues differently in the course of an opponent's unfolding action.