AI-powered bat tracking debuts markerless swing analysis in baseball

A new video-only biomechanics system from Theia promises lab-grade swing analysis without markers or wearable gear, letting teams study the full swing in real baseball environments. Theia announced a commercially available platform that analyzes bat trajectory and full-body biomechanics together, designed to operate in standard cages and on actual fields. The system requires no reflective markers, wearables, or special equipment attached to the bat or the player, expanding access to advanced biomechanics for coaches and players who train in normal environments.

The platform relies on deep-learning models trained on millions of movement data points to deliver a complete 3D bat path, attack angle, sequencing, and body motion in one workflow. It works with standard high-speed video, and Theia says the workflow can run in the background once cameras are placed and calibrated, allowing coaches to record sessions as usual while the software analyzes the data automatically. Marcus Brown, Theia’s chief executive, emphasized that video-only tracking helps teams avoid the behavioral changes that often accompany sensor-based tools: "Using only video means teams get lab-grade biomechanics data that previously required a full lab setup, but without special suits, reflective markers, or hardware mounted to the bat or the player."

Independent testing across more than 2,000 swings showed median bat-plane angle differences of less than 3 degrees when compared with marker-based systems, suggesting the markerless approach can yield consistent results in real-training environments. Driveline Baseball and the PLNU Padres Biomechanics Lab conducted the field tests in professional and collegiate settings, indicating the technology can scale to roster-wide assessments without disrupting practice tempo. The tests demonstrated that the system can capture full swing data in cages and on the field with little to no disruption to players’ routines.

Why video-only tracking works in real baseball settings Many existing tools rely on sensors or suits that can alter how an athlete moves, potentially skewing results. Brown described why video-only tracking matters for day-to-day coaching. "Using only video means teams get lab-grade biomechanics data that previously required a full lab setup, but without special suits, reflective markers, or hardware mounted to the bat or the player," he said. The system runs in the background once cameras are placed and calibrated, coaches record sessions as usual, and the analysis processes automatically. "Until now, full swing analysis meant choosing between bat-only tools or biomechanics labs that couldn't scale. Our new markerless technology changes that. Teams can now see the complete swing picture for every hitter using one system in an environment that matches their individual needs."

How AI bat and body tracking improves player performance A complete swing view gives coaches the chance to link body motion to bat results, enabling more targeted development. Brown explained that Theia’s approach helps identify how sequencing, posture, timing, and rotation relate to the bat’s path, speed, and contact quality. When coaches can connect a player’s movement patterns to the resulting swing outcomes, they can pinpoint the specific mechanics driving performance and track improvements over time with consistent, repeatable data. This capability is intended to translate mechanical work in the cage into more reliable on-field results and to support individualized training plans.

What players experience when teams use Theia's system Players benefit from not having anything attached to their bodies or the bat. They train in their regular spaces, swinging as they normally would, while the software provides precise, personalized feedback to coaches. Driveline Baseball and the Padres Biomechanics Lab cited the value of linking granular biomechanical data to practical adjustments, noting that the system's automation reduces the friction that can slow adoption of advanced analytics in routine practice. The goal is to deliver clearer insight into why a hitter’s swing performs a certain way and how to fine-tune it over time without altering training routines.

The road ahead for AI in sports performance Brown said Theia’s markerless system builds on more than a decade of research and more than 50 peer-reviewed validation studies in markerless motion tracking, reflecting a broader trend toward integrated, low-friction analytics in sports. The company positions the technology as a foundation for more individualized development plans, enabling coaches to monitor changes in sequencing, posture, and timing as they relate to swing grade, power development, and consistency across a lineup.

In context: automation and analytics in baseball The emergence of markerless swing analysis arrives amid a broader push toward data-driven innovation in baseball. The industry has been expanding access to high-fidelity motion data beyond traditional lab settings, and teams increasingly seek scalable systems that fit real-world practice environments. As analytics tools become more integrated into day-to-day coaching, players at all levels may see more personalized guidance based on continuous feedback from footage-only analysis. In related news, MLB has been exploring automation in other facets of the game, with discussions around officiating technologies for the 2026 season that could extend automated analytics into decision-making on the field.

Theia says the combination of video-based bat tracking and full-body sequencing offers a new model for evaluating hitters, one that keeps training natural and data-rich. If teams adopt the technology widely, it could influence how rosters are built, how hitters are developed from a young age, and how in-game adjustments are made in real time. As the field continues to evolve, researchers and practitioners will be watching closely to see how markerless biomechanics influence training decisions, player longevity, and performance outcomes across levels of competition.