diff --git a/osu.Desktop/LegacyIpc/LegacyTcpIpcProvider.cs b/osu.Desktop/LegacyIpc/LegacyTcpIpcProvider.cs
index 97a4c57bf0..10761bc315 100644
--- a/osu.Desktop/LegacyIpc/LegacyTcpIpcProvider.cs
+++ b/osu.Desktop/LegacyIpc/LegacyTcpIpcProvider.cs
@@ -77,10 +77,9 @@ private object onLegacyIpcMessageReceived(object message)
                 case LegacyIpcDifficultyCalculationRequest req:
                     try
                     {
-                        var ruleset = getLegacyRulesetFromID(req.RulesetId);
-
+                        WorkingBeatmap beatmap = new FlatFileWorkingBeatmap(req.BeatmapFile);
+                        var ruleset = beatmap.BeatmapInfo.Ruleset.CreateInstance();
                         Mod[] mods = ruleset.ConvertFromLegacyMods((LegacyMods)req.Mods).ToArray();
-                        WorkingBeatmap beatmap = new FlatFileWorkingBeatmap(req.BeatmapFile, _ => ruleset);
 
                         return new LegacyIpcDifficultyCalculationResponse
                         {
diff --git a/osu.Game/Beatmaps/FlatFileWorkingBeatmap.cs b/osu.Game/Beatmaps/FlatFileWorkingBeatmap.cs
index 163da12b2e..cd8aa31ead 100644
--- a/osu.Game/Beatmaps/FlatFileWorkingBeatmap.cs
+++ b/osu.Game/Beatmaps/FlatFileWorkingBeatmap.cs
@@ -7,7 +7,6 @@
 using osu.Framework.Graphics.Textures;
 using osu.Game.Beatmaps.Formats;
 using osu.Game.IO;
-using osu.Game.Rulesets;
 using osu.Game.Skinning;
 
 namespace osu.Game.Beatmaps
@@ -20,18 +19,16 @@ public class FlatFileWorkingBeatmap : WorkingBeatmap
     {
         private readonly Beatmap beatmap;
 
-        public FlatFileWorkingBeatmap(string file, Func<int, Ruleset> rulesetProvider, int? beatmapId = null)
-            : this(readFromFile(file), rulesetProvider, beatmapId)
+        public FlatFileWorkingBeatmap(string file, int? beatmapId = null)
+            : this(readFromFile(file), beatmapId)
         {
         }
 
-        private FlatFileWorkingBeatmap(Beatmap beatmap, Func<int, Ruleset> rulesetProvider, int? beatmapId = null)
+        private FlatFileWorkingBeatmap(Beatmap beatmap, int? beatmapId = null)
             : base(beatmap.BeatmapInfo, null)
         {
             this.beatmap = beatmap;
 
-            beatmap.BeatmapInfo.Ruleset = rulesetProvider(beatmap.BeatmapInfo.Ruleset.OnlineID).RulesetInfo;
-
             if (beatmapId.HasValue)
                 beatmap.BeatmapInfo.OnlineID = beatmapId.Value;
         }