---
phase: 03-alias-systems
plan: 02
subsystem: data-pipeline
tags: [mls, wnba, nwsl, canonicalization, aliases, teams, stadiums]

# Dependency graph
requires:
  - phase: 02.1-additional-sports-stadiums
    provides: MLS_TEAMS, WNBA_TEAMS, NWSL_TEAMS dicts with stadium data
  - phase: 03-alias-systems/03-01
    provides: NFL canonicalization patterns, division mapping approach
provides:
  - MLS teams canonicalized (30 teams in Eastern/Western conferences)
  - WNBA teams canonicalized (13 teams)
  - NWSL teams canonicalized (13 teams)
  - Team abbreviation aliases for all secondary sports
  - Stadium historical aliases for all secondary sports
affects: [04-canonical-linking, game-resolution, stadium-matching]

# Tech tracking
tech-stack:
  added: []
  patterns: [conference-only-divisions, shared-venue-aliases]

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

key-decisions:
  - "MLS/WNBA/NWSL use conference-only structure (no divisions) - mapped to (conference, None)"
  - "WNBA/NWSL share venues with NBA/MLS - minimal new stadium aliases needed"
  - "Added arena_key='arena' for WNBA to match venue field naming"

patterns-established:
  - "All 7 sports now follow consistent canonicalization patterns"
  - "Conference-only sports use (conference_id, None) for division mapping"

issues-created: []

# Metrics
duration: 5 min
completed: 2026-01-10
---

# Phase 3 Plan 02: Secondary Sports Canonicalization Summary

**MLS, WNBA, NWSL added to canonicalization pipeline with 56 total new teams, 23 abbreviation aliases, and 15 stadium aliases**

## Performance

- **Duration:** 5 min
- **Started:** 2026-01-10T15:38:30Z
- **Completed:** 2026-01-10T15:43:56Z
- **Tasks:** 3
- **Files modified:** 3

## Accomplishments
- MLS canonicalized with 30 teams (Eastern/Western conferences) + 10 aliases + 8 stadium aliases
- WNBA canonicalized with 13 teams + 6 aliases + 4 stadium aliases
- NWSL canonicalized with 13 teams + 7 aliases + 3 stadium aliases
- Total team count now 180 across all 7 sports (NBA: 30, MLB: 30, NHL: 32, NFL: 32, MLS: 30, WNBA: 13, NWSL: 13)

## Task Commits

Each task was committed atomically:

1. **Task 1: Add MLS to canonicalization pipeline** - `b6a913d` (feat)
2. **Task 2: Add WNBA to canonicalization pipeline** - `285bc07` (feat)
3. **Task 3: Add NWSL to canonicalization pipeline** - `81f620d` (feat)

**Plan metadata:** (pending)

## Files Created/Modified
- `Scripts/canonicalize_teams.py` - Added imports, division dicts, sport_mappings for MLS, WNBA, NWSL
- `Scripts/canonicalize_games.py` - Added 23 team abbreviation aliases across 3 sports
- `Scripts/canonicalize_stadiums.py` - Added 15 stadium historical aliases across 3 sports

## Decisions Made
- MLS/WNBA/NWSL use conference-only structure (no divisions) - mapped to (conference_id, None)
- WNBA/NWSL share venues with NBA/MLS - only added sport-specific aliases where needed
- Added arena_key='arena' for WNBA to match venue field naming convention

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered

None

## Next Phase Readiness
- Phase 3 complete - all 7 sports now have alias support
- 180 teams canonicalized with full conference/division structure
- Ready for Phase 4: Canonical Linking

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