---
phase: 03-alias-systems
plan: 01
subsystem: data-pipeline
tags: [nfl, canonicalization, aliases, teams, stadiums]

# Dependency graph
requires:
  - phase: 01-script-architecture
    provides: NFL_TEAMS dict in nfl.py, canonicalization script patterns
  - phase: 02-stadium-foundation
    provides: NFL stadium data with coordinates
provides:
  - NFL teams canonicalized with division structure (32 teams)
  - NFL team abbreviation aliases for game resolution (11 aliases)
  - NFL stadium historical aliases for sponsorship/name changes (14 stadiums)
affects: [04-canonical-linking, game-resolution, stadium-matching]

# Tech tracking
tech-stack:
  added: []
  patterns: [team-abbrev-aliases, historical-stadium-aliases, division-mapping]

key-files:
  created: []
  modified:
    - Scripts/canonicalize_teams.py
    - Scripts/canonicalize_games.py
    - Scripts/canonicalize_stadiums.py

key-decisions:
  - "Used same division ID format as other sports: nfl_afc, nfl_afc_east, etc."
  - "Included historical relocation aliases (OAK→LV, SD→LAC, STL→LAR) for backward compatibility"
  - "Only added stadium aliases for venues with actual name changes (skipped Soldier Field, Lambeau, etc.)"

patterns-established:
  - "NFL follows same canonicalization patterns as MLB, NBA, NHL"
  - "Team abbreviation aliases handle both historical relocations and data source variations"

issues-created: []

# Metrics
duration: 4 min
completed: 2026-01-10
---

# Phase 3 Plan 01: NFL Canonicalization Summary

**NFL added to canonicalization pipeline with 32 teams, 11 abbreviation aliases, and 14 stadium historical aliases**

## Performance

- **Duration:** 4 min
- **Started:** 2026-01-10T15:33:15Z
- **Completed:** 2026-01-10T15:36:49Z
- **Tasks:** 3
- **Files modified:** 3

## Accomplishments
- NFL teams canonicalized with full AFC/NFC division structure (32 teams)
- NFL team abbreviation aliases added for game resolution (handles JAC/JAX, relocations, etc.)
- NFL stadium historical aliases added for sponsorship changes (Heinz Field→Acrisure, FedExField→Northwest Stadium, etc.)

## Task Commits

Each task was committed atomically:

1. **Task 1: Add NFL to canonicalize_teams.py** - `d4d0d95` (feat)
2. **Task 2: Add NFL team abbreviation aliases to canonicalize_games.py** - `41496b6` (feat)
3. **Task 3: Add NFL stadium historical aliases to canonicalize_stadiums.py** - `90c9cef` (feat)

**Plan metadata:** (pending)

## Files Created/Modified
- `Scripts/canonicalize_teams.py` - Added NFL_TEAMS import, NFL_DIVISIONS dict, sport_mappings entry
- `Scripts/canonicalize_games.py` - Added 11 NFL entries to TEAM_ABBREV_ALIASES
- `Scripts/canonicalize_stadiums.py` - Added 14 NFL stadium entries to HISTORICAL_STADIUM_ALIASES

## Decisions Made
- Used same division ID format as other sports (nfl_afc, nfl_afc_east, etc.)
- Included historical relocation aliases (OAK→LV, SD→LAC, STL→LAR) for backward compatibility with older data
- Only added stadium aliases for venues with actual name changes (skipped Soldier Field, Lambeau Field, etc. that haven't changed)

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered

None

## Next Phase Readiness
- NFL canonicalization complete, ready for game resolution testing
- Ready for 03-02-PLAN.md (MLS, WNBA, NWSL canonicalization)

---
*Phase: 03-alias-systems*
*Completed: 2026-01-10*