The purpose of this study was to investigate the relationship between baseball expertise and movement correction efficiency in a coincidence timing task that included unexpected changes in target velocity. In particular, we focused on the rate of movement timing correction that is applied to counter unexpected change in the velocity of a moving target under given time constraints. The participants comprised baseball experts (n=11) and novices (n=11). The task was to manually press a button coinciding with the arrival of a moving target, running on a straight trackway. The target moved from one end of the trackway at a constant velocity, and its velocity was increased or decreased in some trials when it reached the other end of the track with a moving target velocity change (TAVC) from 100 to 300ms. The differences in the rate of movement timing correction between the two groups were more evident when the velocity decreased than when it increased. The rate of movement timing correction for the experts was significantly higher than that for the novices under the 100ms and 300ms TAVC conditions. These results indicate that baseball experts can correct movement timing more efficiently than novices when velocity decreases ; this suggests that efficient movement timing correction in response to an unexpected velocity change is one of the characteristics of baseball expertise.