Towards Comprehensive Basketball Understanding
Organizations: School of Mathematical Sciences, Peking University, China · School of Artificial Intelligence, Shanghai Jiao Tong University, China
Abstract
Understanding a basketball game requires recognizing events, localizing actions, identifying players, and relating these to structured game knowledge. Existing benchmarks primarily evaluate these abilities one at a time, leaving the interactions among these abilities under-explored. We introduce BasketballBench, a multimodal benchmark comprising 7,980 questions across ten tasks in text, image, and video. It is built from the 2025-2026 NBA season and includes official playby-play, rosters and profiles for 530 active players, and 2,501 possession-level broadcast clips. We further propose BasketballSkills, an agent that composes eight basketball-specific perception and retrieval tools under four reusable skills that specify tool order, evidence bindings, and stopping conditions. Experiments show that current MLLMs struggle particularly on questions requiring the integration of multiple capabilities, whereas BasketballSkills outperforms them, highlighting the effectiveness of explicitly composing domain-specific capabilities for comprehensive basketball understanding.
Figures & tables
| Index | Task | Input | Samples | Output | Primary capability |
|---|---|---|---|---|---|
| Q1 | Basketball Knowledge QA | Text | 1,200 | Multiple Choice | Domain Knowledge Grounding |
| Q2 | Match-Situation QA | Text | 1,200 | Multiple Choice | Contextual Retrieval |
| Q3 | Player Image Knowledge QA | Image | 400 | Multiple Choice | Domain Knowledge Grounding |
| Q4 | Scorebug Reading QA | Image | 200 | Structured Text | Broadcast Understanding |
| Q5 | Action Localization QA | Video | 600 | Multiple Choice | Spatial Understanding |
| Q6 | Action Identification QA | Video | 500 | Multiple Choice | Player Identification |
| Model | Q5 | Q6 | ||||
|---|---|---|---|---|---|---|
| Raw | Target | Raw | Target | |||
| GPT-5.4 | 57.2 | 61.5 | +4.3 | 85.4 | 97.0 | +11.6 |
| Claude Sonnet 5 | 23.5 | 33.7 | +10.2 | 55.8 | 84.4 | +28.6 |
| Gemini 3.5 Flash | 41.5 | 47.8 | +6.3 | 78.2 | 94.6 | +16.4 |
| Qwen3.5-9B | 19.7 | 36.3 | +16.7 | 47.2 | 85.8 | +38.6 |
| Molmo2-8B | 18.8 | 21.5 | +2.7 | 32.8 | 45.0 | +12.2 |
Appendix figures & tables7 assets
Supplementary material from the paper’s appendix.
Appendix
| Data Category | Coverage | Scale |
|---|---|---|
| Teams | All current NBA teams | 30 teams |
| Players | Player profiles, including a small number of box-score-only stub records | 633 players |
| Seasonal schedules | All 2025–2026 games across PRE, REG, IST, PIT, and PST | 1,423 games |
| Detailed game records | Team-, player-, and period-level box scores for all regular-season games | 1,230 games |
| Player seasons | Player–team affiliations by season and competition type, covering season years 2012–2025 | 7,940 records |
| Player-season statistics | Season totals and per-game averages across the collected statistical fields | 15,880 rows |
| Model | Basketball AP@50:95 | Player AP@50:95 |
|---|---|---|
| Original RF-DETR Medium | 0.1734 | 0.6029 |
| Fine-tuned RF-DETR Medium | 0.5122 | 0.7886 |
| Improvement | +0.3388 | +0.1857 |
| Class ID | Shot zone | Training examples | Weight |
|---|---|---|---|
| 0 | Above the Break 3 | 4,592 | 0.5069 |
| 1 | Restricted Area | 3,471 | 0.6706 |
| 2 | Left Corner 3 | 755 | 3.083 |
| 3 | Right Corner 3 | 695 | 3.3492 |
| 4 | Mid-Range | 1,602 | 1.453 |
| 5 | In The Paint (Non-RA) | 2,851 | 0.8164 |
| Model | Team Acc. | Score Acc. | Clock Acc. |
|---|---|---|---|
| GPT-5.4 | 95.5 | 99.0 | 97.0 |
| Claude Sonnet 5 | 94.5 | 99.0 | 97.0 |
| Gemini 3.5 Flash | 95.5 | 98.0 | 97.0 |
| Qwen2.5-VL-7B | 72.0 | 96.0 | 95.0 |
| Qwen3.5-4B | 76.5 | 98.0 | 91.0 |
| Qwen3.5-9B | 85.5 | 96.0 | 59.0 |
| Ground truth | RA | Paint | ATB3 | LC3 | RC3 | Mid | U |
|---|---|---|---|---|---|---|---|
| Restricted Area | 74.0 | 6.0 | 1.5 | 1.0 | 0.0 | 9.0 | 8.5 |
| Paint (Non-RA) | 30.5 | 44.0 | 0.0 | 0.0 | 0.0 | 21.0 | 4.5 |
| Above Break 3 | 1.0 | 0.0 | 64.0 | 15.0 | 4.0 | 16.0 | 0.0 |
| Left Corner 3 | 2.5 | 2.0 | 0.0 | 90.0 | 0.0 | 4.0 | 1.5 |
| Right Corner 3 | 3.0 | 0.0 | 1.0 | 2.0 | 83.0 | 8.0 | 3.0 |
| Mid-Range | 8.5 | 16.0 | 4.0 | 3.0 | 3.0 | 64.0 | 1.5 |
| Model | Video Timestamp | Game Clock | ||||||
|---|---|---|---|---|---|---|---|---|
| P-Acc@1s | Acc@1s | Parse | MAE | P-Acc@1s | Acc@1s | Parse | MAE | |
| GPT-5.4 | 69.2 | 69.2 | 100.0 | 1.67 | 86.2 | 85.7 | 99.4 | 1.52 |
| Claude Sonnet 5 | 36.8 | 36.8 | 100.0 | 2.54 | 65.8 ∗ | 65.7 ∗ | 99.9 ∗ | 11.44 ∗ |
| Gemini 3.5 Flash | 57.6 | 55.9 | 97.2 | 1.30 | 74.4 | 70.4 | 94.6 | 2.92 |
| Qwen2.5-VL-7B | 1.1 | 1.1 | 100.0 | 5.96 | 45.0 ∗ | 44.9 ∗ | 99.9 ∗ | 16.33 ∗ |
| Qwen3.5-4B | 52.5 | 51.0 | 97.2 | 1.40 | 46.3 ∗ | 45.8 ∗ | 99.0 ∗ | 30.55 ∗ |
| Model | Type+Participant | Type | PA | Parse | ||||
|---|---|---|---|---|---|---|---|---|
| P | R | F1 | P | R | F1 | |||
| GPT-5.4 | 26.1 | 34.8 | 29.8 | 52.2 | 69.5 | 59.6 | 46.7 | 99.9 |
| Claude Sonnet 5 | 11.3 | 19.5 | 14.3 | 34.6 | 60.0 | 43.9 | 24.5 | 95.5 |
| Gemini 3.5 Flash ∗ | 22.5 | 33.7 | 27.0 | 43.2 | 64.7 | 51.8 | 49.4 | 97.8 |
| Qwen2.5-VL-7B ∗ | 1.3 | 2.1 | 1.6 | 22.7 | 34.9 | 27.5 | 5.1 | 100.0 |
| Qwen3.5-4B ∗ | 6.5 | 11.1 | 8.2 | 30.9 | 53.0 | 39.1 | 20.6 | 100.0 |
Sports Video Analysis
Sports video analysis uses computer vision and multimodal models to track athletes, locate events, and explain tactics in game footage.
See all 80 papers