diff --git a/app/db_engine.py b/app/db_engine.py
index 30e7d7c..bb9c9f0 100644
--- a/app/db_engine.py
+++ b/app/db_engine.py
@@ -1050,8 +1050,75 @@ decision_index = ModelIndex(Decision, (Decision.game, Decision.pitcher), unique=
 Decision.add_index(decision_index)
 
 
+class PlayerSeasonStats(BaseModel):
+    player = ForeignKeyField(Player)
+    team = ForeignKeyField(Team)
+    season = IntegerField()
+
+    # Batting stats
+    games_batting = IntegerField(default=0)
+    pa = IntegerField(default=0)
+    ab = IntegerField(default=0)
+    hits = IntegerField(default=0)
+    hr = IntegerField(default=0)
+    doubles = IntegerField(default=0)
+    triples = IntegerField(default=0)
+    bb = IntegerField(default=0)
+    hbp = IntegerField(default=0)
+    so = IntegerField(default=0)
+    rbi = IntegerField(default=0)
+    runs = IntegerField(default=0)
+    sb = IntegerField(default=0)
+    cs = IntegerField(default=0)
+
+    # Pitching stats
+    games_pitching = IntegerField(default=0)
+    outs = IntegerField(default=0)
+    k = IntegerField(
+        default=0
+    )  # pitcher Ks; spec names this "so (K)" but renamed to avoid collision with batting so
+    bb_allowed = IntegerField(default=0)
+    hits_allowed = IntegerField(default=0)
+    hr_allowed = IntegerField(default=0)
+    wins = IntegerField(default=0)
+    losses = IntegerField(default=0)
+    saves = IntegerField(default=0)
+    holds = IntegerField(default=0)
+    blown_saves = IntegerField(default=0)
+
+    # Meta
+    last_game = ForeignKeyField(StratGame, null=True)
+    last_updated_at = DateTimeField(null=True)
+
+    class Meta:
+        database = db
+        table_name = "player_season_stats"
+
+
+pss_unique_index = ModelIndex(
+    PlayerSeasonStats,
+    (PlayerSeasonStats.player, PlayerSeasonStats.team, PlayerSeasonStats.season),
+    unique=True,
+)
+PlayerSeasonStats.add_index(pss_unique_index)
+
+pss_team_season_index = ModelIndex(
+    PlayerSeasonStats,
+    (PlayerSeasonStats.team, PlayerSeasonStats.season),
+    unique=False,
+)
+PlayerSeasonStats.add_index(pss_team_season_index)
+
+pss_player_season_index = ModelIndex(
+    PlayerSeasonStats,
+    (PlayerSeasonStats.player, PlayerSeasonStats.season),
+    unique=False,
+)
+PlayerSeasonStats.add_index(pss_player_season_index)
+
+
 if not SKIP_TABLE_CREATION:
-    db.create_tables([StratGame, StratPlay, Decision], safe=True)
+    db.create_tables([StratGame, StratPlay, Decision, PlayerSeasonStats], safe=True)
 
 
 class ScoutOpportunity(BaseModel):
diff --git a/app/models/__init__.py b/app/models/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/app/models/season_stats.py b/app/models/season_stats.py
new file mode 100644
index 0000000..bdd7ad1
--- /dev/null
+++ b/app/models/season_stats.py
@@ -0,0 +1,7 @@
+"""PlayerSeasonStats ORM model.
+
+Model is defined in db_engine alongside all other Peewee models; this
+module re-exports it so callers can import from `app.models.season_stats`.
+"""
+
+from ..db_engine import PlayerSeasonStats  # noqa: F401
diff --git a/tests/conftest.py b/tests/conftest.py
new file mode 100644
index 0000000..8d61378
--- /dev/null
+++ b/tests/conftest.py
@@ -0,0 +1,14 @@
+"""Pytest configuration for the paper-dynasty-database test suite.
+
+Sets DATABASE_TYPE=postgresql before any app module is imported so that
+db_engine.py sets SKIP_TABLE_CREATION=True and does not try to mutate the
+production SQLite file during test collection.  Each test module is
+responsible for binding models to its own in-memory database.
+"""
+
+import os
+
+os.environ["DATABASE_TYPE"] = "postgresql"
+# Provide dummy credentials so PooledPostgresqlDatabase can be instantiated
+# without raising a configuration error (it will not actually be used).
+os.environ.setdefault("POSTGRES_PASSWORD", "test-dummy")
diff --git a/tests/test_season_stats_model.py b/tests/test_season_stats_model.py
new file mode 100644
index 0000000..20fc3b8
--- /dev/null
+++ b/tests/test_season_stats_model.py
@@ -0,0 +1,355 @@
+"""Tests for PlayerSeasonStats Peewee model (WP-02).
+
+Unit tests verify model structure and defaults on unsaved instances without
+touching a database. Integration tests use an in-memory SQLite database to
+verify table creation, unique constraints, indexes, and the delta-update
+(increment) pattern.
+
+Note on column naming: the spec labels the pitching strikeout column as
+"so (K)". This model names it `k` to avoid collision with the batting
+strikeout column `so`.
+"""
+
+import pytest
+from peewee import SqliteDatabase, IntegrityError
+
+from app.models.season_stats import PlayerSeasonStats
+from app.db_engine import Rarity, Event, Cardset, MlbPlayer, Player, Team, StratGame
+
+# Dependency order matters for FK resolution.
+_TEST_MODELS = [
+    Rarity,
+    Event,
+    Cardset,
+    MlbPlayer,
+    Player,
+    Team,
+    StratGame,
+    PlayerSeasonStats,
+]
+
+_test_db = SqliteDatabase(":memory:", pragmas={"foreign_keys": 1})
+
+
+@pytest.fixture(autouse=True)
+def setup_test_db():
+    """Bind all models to an in-memory SQLite database, create tables, and
+    tear them down after each test so each test starts from a clean state."""
+    _test_db.bind(_TEST_MODELS)
+    _test_db.create_tables(_TEST_MODELS)
+    yield _test_db
+    _test_db.drop_tables(list(reversed(_TEST_MODELS)), safe=True)
+
+
+# ── Fixture helpers ─────────────────────────────────────────────────────────
+
+
+def make_rarity():
+    return Rarity.create(value=1, name="Common", color="#ffffff")
+
+
+def make_cardset():
+    return Cardset.create(name="2025", description="2025 Season", total_cards=100)
+
+
+def make_player(cardset, rarity, player_id=1):
+    return Player.create(
+        player_id=player_id,
+        p_name="Test Player",
+        cost=100,
+        image="test.png",
+        mlbclub="BOS",
+        franchise="Boston",
+        cardset=cardset,
+        set_num=1,
+        rarity=rarity,
+        pos_1="OF",
+        description="Test",
+    )
+
+
+def make_team(abbrev="TEST", gmid=123456789):
+    return Team.create(
+        abbrev=abbrev,
+        sname=abbrev,
+        lname=f"Team {abbrev}",
+        gmid=gmid,
+        gmname="testuser",
+        gsheet="https://example.com",
+        wallet=1000,
+        team_value=1000,
+        collection_value=1000,
+        season=1,
+    )
+
+
+def make_game(home_team, away_team, season=10):
+    return StratGame.create(
+        season=season,
+        game_type="ranked",
+        away_team=away_team,
+        home_team=home_team,
+    )
+
+
+def make_stats(player, team, season=10, **kwargs):
+    return PlayerSeasonStats.create(player=player, team=team, season=season, **kwargs)
+
+
+# ── Unit: column completeness ────────────────────────────────────────────────
+
+
+class TestColumnCompleteness:
+    """All required columns are present in the model's field definitions."""
+
+    BATTING_COLS = [
+        "games_batting",
+        "pa",
+        "ab",
+        "hits",
+        "hr",
+        "doubles",
+        "triples",
+        "bb",
+        "hbp",
+        "so",
+        "rbi",
+        "runs",
+        "sb",
+        "cs",
+    ]
+    PITCHING_COLS = [
+        "games_pitching",
+        "outs",
+        "k",
+        "bb_allowed",
+        "hits_allowed",
+        "hr_allowed",
+        "wins",
+        "losses",
+        "saves",
+        "holds",
+        "blown_saves",
+    ]
+    META_COLS = ["last_game", "last_updated_at"]
+    KEY_COLS = ["player", "team", "season"]
+
+    def test_batting_columns_present(self):
+        """All batting aggregate columns defined in the spec are present."""
+        fields = PlayerSeasonStats._meta.fields
+        for col in self.BATTING_COLS:
+            assert col in fields, f"Missing batting column: {col}"
+
+    def test_pitching_columns_present(self):
+        """All pitching aggregate columns defined in the spec are present."""
+        fields = PlayerSeasonStats._meta.fields
+        for col in self.PITCHING_COLS:
+            assert col in fields, f"Missing pitching column: {col}"
+
+    def test_meta_columns_present(self):
+        """Meta columns last_game and last_updated_at are present."""
+        fields = PlayerSeasonStats._meta.fields
+        for col in self.META_COLS:
+            assert col in fields, f"Missing meta column: {col}"
+
+    def test_key_columns_present(self):
+        """player, team, and season columns are present."""
+        fields = PlayerSeasonStats._meta.fields
+        for col in self.KEY_COLS:
+            assert col in fields, f"Missing key column: {col}"
+
+    def test_excluded_columns_absent(self):
+        """team_wins and quality_starts are NOT in the model (removed from scope)."""
+        fields = PlayerSeasonStats._meta.fields
+        assert "team_wins" not in fields
+        assert "quality_starts" not in fields
+
+
+# ── Unit: default values ─────────────────────────────────────────────────────
+
+
+class TestDefaultValues:
+    """All integer stat columns default to 0; nullable meta fields default to None."""
+
+    INT_STAT_COLS = [
+        "games_batting",
+        "pa",
+        "ab",
+        "hits",
+        "hr",
+        "doubles",
+        "triples",
+        "bb",
+        "hbp",
+        "so",
+        "rbi",
+        "runs",
+        "sb",
+        "cs",
+        "games_pitching",
+        "outs",
+        "k",
+        "bb_allowed",
+        "hits_allowed",
+        "hr_allowed",
+        "wins",
+        "losses",
+        "saves",
+        "holds",
+        "blown_saves",
+    ]
+
+    def test_all_int_columns_default_to_zero(self):
+        """Every integer stat column defaults to 0 on an unsaved instance."""
+        row = PlayerSeasonStats()
+        for col in self.INT_STAT_COLS:
+            val = getattr(row, col)
+            assert val == 0, f"Column {col!r} default is {val!r}, expected 0"
+
+    def test_last_game_defaults_to_none(self):
+        """last_game FK is nullable and defaults to None."""
+        row = PlayerSeasonStats()
+        assert row.last_game_id is None
+
+    def test_last_updated_at_defaults_to_none(self):
+        """last_updated_at defaults to None."""
+        row = PlayerSeasonStats()
+        assert row.last_updated_at is None
+
+
+# ── Integration: unique constraint ───────────────────────────────────────────
+
+
+class TestUniqueConstraint:
+    """UNIQUE on (player_id, team_id, season) is enforced at the DB level."""
+
+    def test_duplicate_player_team_season_raises(self):
+        """Inserting a second row for the same (player, team, season) raises IntegrityError."""
+        rarity = make_rarity()
+        cardset = make_cardset()
+        player = make_player(cardset, rarity)
+        team = make_team()
+        make_stats(player, team, season=10)
+        with pytest.raises(IntegrityError):
+            make_stats(player, team, season=10)
+
+    def test_same_player_different_season_allowed(self):
+        """Same (player, team) in a different season creates a separate row."""
+        rarity = make_rarity()
+        cardset = make_cardset()
+        player = make_player(cardset, rarity)
+        team = make_team()
+        make_stats(player, team, season=10)
+        row2 = make_stats(player, team, season=11)
+        assert row2.id is not None
+
+    def test_same_player_different_team_allowed(self):
+        """Same (player, season) on a different team creates a separate row."""
+        rarity = make_rarity()
+        cardset = make_cardset()
+        player = make_player(cardset, rarity)
+        team1 = make_team("TM1", gmid=111)
+        team2 = make_team("TM2", gmid=222)
+        make_stats(player, team1, season=10)
+        row2 = make_stats(player, team2, season=10)
+        assert row2.id is not None
+
+
+# ── Integration: delta update pattern ───────────────────────────────────────
+
+
+class TestDeltaUpdatePattern:
+    """Stats can be incremented (delta update) without replacing existing values."""
+
+    def test_increment_batting_stats(self):
+        """Updating pa and hits increments without touching pitching columns."""
+        rarity = make_rarity()
+        cardset = make_cardset()
+        player = make_player(cardset, rarity)
+        team = make_team()
+        row = make_stats(player, team, season=10, pa=5, hits=2)
+
+        PlayerSeasonStats.update(
+            pa=PlayerSeasonStats.pa + 3,
+            hits=PlayerSeasonStats.hits + 1,
+        ).where(
+            (PlayerSeasonStats.player == player)
+            & (PlayerSeasonStats.team == team)
+            & (PlayerSeasonStats.season == 10)
+        ).execute()
+
+        updated = PlayerSeasonStats.get_by_id(row.id)
+        assert updated.pa == 8
+        assert updated.hits == 3
+        assert updated.games_pitching == 0  # untouched
+
+    def test_increment_pitching_stats(self):
+        """Updating outs and k increments without touching batting columns."""
+        rarity = make_rarity()
+        cardset = make_cardset()
+        player = make_player(cardset, rarity)
+        team = make_team()
+        row = make_stats(player, team, season=10, outs=9, k=3)
+
+        PlayerSeasonStats.update(
+            outs=PlayerSeasonStats.outs + 6,
+            k=PlayerSeasonStats.k + 2,
+        ).where(
+            (PlayerSeasonStats.player == player)
+            & (PlayerSeasonStats.team == team)
+            & (PlayerSeasonStats.season == 10)
+        ).execute()
+
+        updated = PlayerSeasonStats.get_by_id(row.id)
+        assert updated.outs == 15
+        assert updated.k == 5
+        assert updated.pa == 0  # untouched
+
+    def test_last_game_fk_is_nullable(self):
+        """last_game FK can be set to a StratGame instance or left NULL."""
+        rarity = make_rarity()
+        cardset = make_cardset()
+        player = make_player(cardset, rarity)
+        team = make_team()
+        row = make_stats(player, team, season=10)
+        assert row.last_game_id is None
+
+        game = make_game(home_team=team, away_team=team)
+        PlayerSeasonStats.update(last_game=game).where(
+            PlayerSeasonStats.id == row.id
+        ).execute()
+
+        updated = PlayerSeasonStats.get_by_id(row.id)
+        assert updated.last_game_id == game.id
+
+
+# ── Integration: index existence ─────────────────────────────────────────────
+
+
+class TestIndexExistence:
+    """Required indexes on (team_id, season) and (player_id, season) exist in SQLite."""
+
+    def _get_index_columns(self, db, table):
+        """Return a set of frozensets, each being the column set of one index."""
+        indexes = db.execute_sql(f"PRAGMA index_list({table})").fetchall()
+        result = set()
+        for idx in indexes:
+            idx_name = idx[1]
+            cols = db.execute_sql(f"PRAGMA index_info({idx_name})").fetchall()
+            result.add(frozenset(col[2] for col in cols))
+        return result
+
+    def test_unique_index_on_player_team_season(self, setup_test_db):
+        """A unique index covering (player_id, team_id, season) exists."""
+        index_sets = self._get_index_columns(setup_test_db, "player_season_stats")
+        assert frozenset({"player_id", "team_id", "season"}) in index_sets
+
+    def test_index_on_team_season(self, setup_test_db):
+        """An index covering (team_id, season) exists."""
+        index_sets = self._get_index_columns(setup_test_db, "player_season_stats")
+        assert frozenset({"team_id", "season"}) in index_sets
+
+    def test_index_on_player_season(self, setup_test_db):
+        """An index covering (player_id, season) exists."""
+        index_sets = self._get_index_columns(setup_test_db, "player_season_stats")
+        assert frozenset({"player_id", "season"}) in index_sets