Previous research (French, Spurgeon, and Nevett, 1995) has shown that expert youth baseball players exhibit superior performance of baseball skills during games. In addition, the youth expert baseball players were significantly taller, had longer legs and arms, and greater shoulder and hip width. Thus, a portion of the differences in performance may have been due to differences in body size. The purpose of this study was to compare the movement patterns for throwing and the combination of fielding and throwing in expert and novice baseball players from ages 7 to 10. Participants were 79 male Little League players (twenty-three 7-year olds, twenty-one 8-year olds, twenty 9-year olds and fifteen 10-year olds) who were a subset of participants of a larger study examining other aspects of developing expertise in youth baseball. Process characteristics of players throwing for distance and fielding and throwing were observed. Separate Kruskal-Wallis tests were conducted to determine differences between expert and novice players on each of the five throwing components and on each of the six fielding and throwing components. The alpha level was set at p < .05. Significant differences were observed between expert and novice skilled players for the preparatory arm-backswing, humerus, and forearm components of the overarm throw. Expert players were more advanced at each age. Significant differences were observed between expert and novice players for the approach and control components of fielding. Expert 7- and 8-year olds charged the ball more timidly than expert 9- and 10-year olds. The 7- and 10-year old expert players used a one-handed scoop successfully to field the ball whereas their novice peers fielded the ball with two hands. Differences in movement patterns between expert and novice youth baseball players emerged at 7 years of age. The findings in the present study suggest that expert-novice differences in skill performance emerge during very early participation in both the product and process measures of performance. Superior performance of experts in product measures of performance are likely due to larger body size, greater accumulation of practice, and more advanced movement patterns.Keyword(s): athletics/sports, performance, youth sports