diff --git a/osu.Game/Database/RealmAccess.cs b/osu.Game/Database/RealmAccess.cs
index cd97bb6430..12d1753b9b 100644
--- a/osu.Game/Database/RealmAccess.cs
+++ b/osu.Game/Database/RealmAccess.cs
@@ -84,8 +84,9 @@ public class RealmAccess : IDisposable
         /// 32   2023-07-09    Populate legacy scores with the ScoreV2 mod (and restore TotalScore to the legacy total for such scores) using replay files.
         /// 33   2023-08-16    Reset default chat toggle key binding to avoid conflict with newly added leaderboard toggle key binding.
         /// 34   2023-08-21    Add BackgroundReprocessingFailed flag to ScoreInfo to track upgrade failures.
+        /// 35   2023-09-01    Add LegacyOnlineID to ScoreInfo. Move osu_scores_*_high IDs stored in OnlineID to LegacyOnlineID. Reset anomalous OnlineIDs.
         /// </summary>
-        private const int schema_version = 34;
+        private const int schema_version = 35;
 
         /// <summary>
         /// Lock object which is held during <see cref="BlockAllOperations"/> sections, blocking realm retrieval during blocking periods.
@@ -1031,6 +1032,24 @@ void convertOnlineIDs<T>() where T : RealmObject
 
                     break;
                 }
+
+                case 35:
+                {
+                    foreach (var score in migration.NewRealm.All<ScoreInfo>())
+                    {
+                        if (score.OnlineID > 0)
+                        {
+                            score.LegacyOnlineID = score.OnlineID;
+                            score.OnlineID = -1;
+                        }
+                        else
+                        {
+                            score.LegacyOnlineID = score.OnlineID = -1;
+                        }
+                    }
+
+                    break;
+                }
             }
 
             Logger.Log($"Migration completed in {stopwatch.ElapsedMilliseconds}ms");
diff --git a/osu.Game/Scoring/ScoreInfo.cs b/osu.Game/Scoring/ScoreInfo.cs
index 8531408555..992271d072 100644
--- a/osu.Game/Scoring/ScoreInfo.cs
+++ b/osu.Game/Scoring/ScoreInfo.cs
@@ -100,9 +100,25 @@ public class ScoreInfo : RealmObject, IHasGuidPrimaryKey, IHasRealmFiles, ISoftD
 
         public double? PP { get; set; }
 
+        /// <summary>
+        /// The online ID of this score.
+        /// </summary>
+        /// <remarks>
+        /// In the osu-web database, this ID (if present) comes from the new <c>solo_scores</c> table.
+        /// </remarks>
         [Indexed]
         public long OnlineID { get; set; } = -1;
 
+        /// <summary>
+        /// The legacy online ID of this score.
+        /// </summary>
+        /// <remarks>
+        /// In the osu-web database, this ID (if present) comes from the legacy <c>osu_scores_*_high</c> tables.
+        /// This ID is also stored to replays set on osu!stable.
+        /// </remarks>
+        [Indexed]
+        public long LegacyOnlineID { get; set; } = -1;
+
         [MapTo("User")]
         public RealmUser RealmUser { get; set; } = null!;