Background: Although ulnar collateral ligament reconstruction (UCLR) is commonly performed in Major League Baseball (MLB) pitchers, few studies have evaluated advanced analytical data in the context of return to play (RTP) after injury. Traditional postoperative outcomes have not reliably predicted players return to their preoperative performance level. Pitch movements and release extension, defined as the raw horizontal and/or vertical movement of a pitch, and distance off the pitcher’s mound a pitcher releases the pitch are all key elements professional pitchers rely upon for effectiveness. Existing literature has demonstrated a varying degree of impact of some objective advanced measurements, such as spin rate and pitch movements, using a pitching tracking system that has been recently implemented and used for analytical data collection in professional baseball. The present study is one of the first to explore the impact of UCL reconstruction on horizontal and vertical pitch movement as well as pitch release extension. The study is also the first comparison of those advanced measurements between MLB pitchers who returned with sustained performance and those who were unable to return to preinjury performance levels for sustained time. Methods: 113 MLB pitchers who underwent UCLR between 2016 and 2022 were identified via public record. The identified cohort was separated into those who returned with sustained levels of play, defined as throwing >500 pitches per season for multiple seasons following UCLR, and those who did not. The Statcast system was utilized to collect horizontal movement, vertical movement, and release extension for 4FB, 2FB, CU, and SL in the preinjury year as well as in each of the 2 years after following UCLR. Results: 70 pitchers (62%) returned to the MLB level after UCLR. There was significant change in vertical movement for 4FB preoperatively compared to 1-year postoperatively (p<0.05). Pitchers who returned to the MLB with sustained level of performance demonstrated a statistical increase (p<0.05) in release extension for all pitch types in the first postoperative season when compared to those who returned without longevity, but the observed changes in release extension was only maintained in 4FB in the second postoperative season. Conclusion: MLB pitchers who underwent UCLR and returned to the MLB level demonstrated a significant change in pitch release extension with all pitch types two years after surgery. The MLB pitchers who returned to the MLB level after UCLR and achieved longevity averaged a greater release extension postoperatively than those who did not.