diff --git a/src/models/player.js b/src/models/player.js
index 733c138..5f3f2c7 100644
--- a/src/models/player.js
+++ b/src/models/player.js
@@ -17,12 +17,27 @@ function getPlayerFromDB(pdgaNumber) {
 function savePlayerToDB(playerData) {
   return new Promise((resolve, reject) => {
     db.run(
-      `INSERT OR REPLACE INTO players (pdga_number, name, current_rating, rating_change, last_updated)
-       VALUES (?, ?, ?, ?, datetime('now'))`,
+      // UPSERT (not INSERT OR REPLACE): updating in place preserves columns not
+      // listed here — predicted_rating, std_dev, last_round_update,
+      // excluded_rounds_count, cutoff_rating. INSERT OR REPLACE would delete the
+      // existing row and reset those to their DEFAULT (NULL).
+      `INSERT INTO players (pdga_number, name, current_rating, rating_change, last_updated)
+       VALUES (?, ?, ?, ?, datetime('now'))
+       ON CONFLICT(pdga_number) DO UPDATE SET
+         name = excluded.name,
+         current_rating = excluded.current_rating,
+         rating_change = excluded.rating_change,
+         last_updated = excluded.last_updated`,
       [playerData.pdgaNumber, playerData.name, playerData.rating, playerData.ratingChange],
       function(err) {
-        if (err) reject(err);
-        else resolve(this.lastID);
+        if (err) return reject(err);
+        // node-sqlite3 leaves lastID = 0 when ON CONFLICT triggers an UPDATE.
+        // Fall back to a SELECT to get the real id in that case.
+        if (this.lastID !== 0) return resolve(this.lastID);
+        db.get('SELECT id FROM players WHERE pdga_number = ?', [playerData.pdgaNumber], (err2, row) => {
+          if (err2) reject(err2);
+          else resolve(row ? row.id : 0);
+        });
       }
     );
   });