diff --git a/osu.Game/Beatmaps/Formats/LegacyStoryboardDecoder.cs b/osu.Game/Beatmaps/Formats/LegacyStoryboardDecoder.cs
index 9ba4d7b05e..35576e0f33 100644
--- a/osu.Game/Beatmaps/Formats/LegacyStoryboardDecoder.cs
+++ b/osu.Game/Beatmaps/Formats/LegacyStoryboardDecoder.cs
@@ -72,7 +72,7 @@ namespace osu.Game.Beatmaps.Formats
                 ++depth;
             }
 
-            line = line.Substring(depth);
+            line = lineSpan.ToString();
 
             decodeVariables(ref line);