Why sport became a data problem

Sport has always involved numbers: goals, times, distances. What has changed is granularity. Instead of recording a handful of events per match, modern systems capture the position of every player and the ball many times per second, along with detailed event data describing each pass, shot, tackle and press. Wearables add heart rate, acceleration and distance covered in training.

That shift turned sport into a spatial and temporal data problem, which is exactly the kind I enjoy. As a geomatics engineer, I recognise many of the techniques: trajectory analysis, spatial density estimation, Voronoi partitions of space. A football pitch is a small, very well-instrumented map.

The community around events like the MIT Sloan Sports Analytics Conference and data providers such as Hudl StatsBomb have helped make analytics a mainstream part of professional sport, and some providers have released free datasets that let students and independent analysts practise on real match data.

How the core techniques work

Sports analytics rests on a few technical building blocks:

  • Computer vision tracking: object detection models locate players, referees and the ball in broadcast or fixed-camera video, and multi-object tracking links detections across frames. Camera calibration maps image pixels to pitch coordinates, a problem closely related to photogrammetry.
  • Pose estimation: models like OpenPose estimate body keypoints from video, enabling analysis of running mechanics, shooting technique or bowling actions without markers.
  • Event data modelling: expected goals (xG) models estimate the probability that a shot results in a goal, based on features like distance, angle, body part and defensive pressure. They are typically logistic regression or gradient-boosted models trained on large shot datasets.
  • Action valuation: frameworks like VAEP value every on-ball action by how much it changes the probability of scoring and conceding in the near future, giving credit to passes and dribbles that build attacks, not just to the final shot.
  • Tactical modelling: graph neural networks represent players as nodes and their relationships as edges. Google DeepMind's work with Liverpool FC on TacticAI, published in Nature Communications, used this approach to analyse corner kicks and suggest tactical adjustments that experts often preferred.
  • Load and injury modelling: time-series models relate training load, sleep and recovery data to injury risk and readiness.

A simple xG model illustrates the flavour of this work:

features = ["distance", "angle", "is_header", "defenders_in_cone"]
model = GradientBoostingClassifier().fit(shots[features], shots["goal"])
shots["xg"] = model.predict_proba(shots[features])[:, 1]

Real-world uses across the game

  • Scouting and recruitment: clubs filter large player databases using performance models before sending scouts to watch. This helps smaller clubs find undervalued talent.
  • Opposition analysis: automated tagging of video clips by phase of play saves analysts hours of manual work.
  • Set-piece design: corners and free kicks are discrete, repeatable situations, which makes them well suited to modelling and simulation.
  • Athlete development: in athletics, swimming and cricket, pose estimation and sensor data provide technique feedback that once required lab equipment.
  • Officiating: semi-automated offside technology and goal-line systems combine tracking and computer vision to support referees.
  • Fan engagement: live win probabilities, personalised highlights and automated commentary in multiple languages.

The African opportunity

Africa produces extraordinary sporting talent, yet much of it is discovered late, informally or by foreign scouts. Many domestic leagues and academies lack video infrastructure, let alone tracking data. That gap is also an opportunity.

  • Smartphone-based analysis: pose estimation and basic tracking can run on footage from a single phone or low-cost camera, making technique analysis viable for academies and school programmes.
  • Talent identification: standardised, low-cost testing combined with simple data platforms can create fairer pathways for players outside major cities.
  • League data infrastructure: structured event data for domestic leagues increases their visibility to clubs, broadcasters and sponsors, potentially raising the value of local players and competitions.
  • Local tech talent: sports analytics is a great domain for developers to build portfolios. I often encourage mentees at BuildWithMMO to work on projects with public football datasets because the problems are intuitive, visual and technically rich.

Risks and limitations

  • Athlete privacy: biometric and health data from wearables is sensitive. Players, especially young academy players, must understand and consent to how their data is used, and ownership should be clear when players transfer.
  • Exploitation of young players: data-driven scouting could intensify the problem of young African players being moved abroad under poor conditions. Data should support player welfare, not just transfers.
  • Context blindness: models trained on top European leagues may not transfer to different playing styles, pitch conditions or levels of competition.
  • Over-quantification: metrics like xG are useful summaries but not the whole truth. Coaches' tacit knowledge, team chemistry and psychology resist easy measurement.
  • Data inequality: rich clubs with proprietary tracking data gain advantages that can widen competitive gaps.

Getting started: guidance for teams and clubs

  1. Start with questions coaches care about. Analytics fails when it answers questions nobody asked. Sit with coaching staff first.
  2. Collect consistent video. A fixed, elevated camera recording every match is the foundation for almost everything else.
  3. Use open datasets to build skills. Free event datasets let analysts develop and validate models before investing in data collection.
  4. Keep outputs simple. A clear clip with one annotated insight often beats a complex dashboard.
  5. Write a data policy. Define consent, access, retention and what happens to player data when someone leaves.

For developers building the platforms behind this work, the architecture is familiar: an ingestion layer for video and sensor feeds, a processing pipeline for detection and tracking, a database of events keyed by match, time and pitch coordinates, and an API that serves clips and metrics to coaches. A Django or FastAPI backend with a spatial database such as PostGIS handles much of this comfortably. The hardest engineering problems tend to be synchronising video with event data and keeping processing costs manageable on limited budgets, so batch processing overnight is often more practical than real-time analysis for smaller clubs.

Key takeaways

  • Tracking, event and wearable data have turned sport into a rich spatio-temporal data problem.
  • Computer vision, pose estimation, expected goals, action valuation and graph neural networks are core techniques.
  • Research like TacticAI shows AI can offer tactical suggestions that experts find useful.
  • Low-cost video and smartphone analysis can bring analytics to African academies and leagues.
  • Protect athlete data, especially for young players, and guard against exploitative scouting.
  • Successful analytics starts with coaches' questions and simple, actionable outputs.

References & further reading

  1. Actions Speak Louder than Goals: Valuing Player Actions in Soccer — arXiv
  2. TacticAI: an AI assistant for football tactics — Nature Communications
  3. OpenPose: Realtime Multi-Person 2D Pose Estimation using Part Affinity Fields — arXiv
  4. Hudl StatsBomb — StatsBomb
  5. MIT Sloan Sports Analytics Conference — MIT Sloan

Cover image: original illustration created for this article. Cited works remain the property of their respective authors and publishers.