diff --git a/app/Actions/Tabulation/EnterPrelimScore.php b/app/Actions/Tabulation/EnterPrelimScore.php
index b9e916f..76536e3 100644
--- a/app/Actions/Tabulation/EnterPrelimScore.php
+++ b/app/Actions/Tabulation/EnterPrelimScore.php
@@ -38,6 +38,11 @@ class EnterPrelimScore
         }
         $prelimDefinition = PrelimDefinition::where('audition_id', $entry->audition->id)->first();
 
+        // Don't allow changes to prelims scores if the entry has a finals score
+        if ($entry->scoreSheets()->count() > 0) {
+            throw new AuditionAdminException('Cannot change prelims scores for an entry that has finals scores');
+        }
+
         // Check that the specified user is assigned to judge this entry in prelims
         $check = DB::table('room_user')
             ->where('user_id', $user->id)