diff --git a/src/libraries/System.Text.Json/src/System/Text/Json/Document/JsonDocument.MetadataDb.cs b/src/libraries/System.Text.Json/src/System/Text/Json/Document/JsonDocument.MetadataDb.cs
index dca61c889c89d8..20cdf3775c0a43 100644
--- a/src/libraries/System.Text.Json/src/System/Text/Json/Document/JsonDocument.MetadataDb.cs
+++ b/src/libraries/System.Text.Json/src/System/Text/Json/Document/JsonDocument.MetadataDb.cs
@@ -381,7 +381,7 @@ internal MetadataDb CopySegment(int startIndex, int endIndex)
                 byte[] newDatabase = new byte[length];
                 _data.AsSpan(startIndex, length).CopyTo(newDatabase);
 
-                Span<int> newDbInts = MemoryMarshal.Cast<byte, int>(newDatabase);
+                Span<int> newDbInts = MemoryMarshal.Cast<byte, int>(newDatabase.AsSpan());
                 int locationOffset = newDbInts[0];
 
                 // Need to nudge one forward to account for the hidden quote on the string.