diff --git a/worldsrv/tournament.go b/worldsrv/tournament.go
index c668c14..ea0527f 100644
--- a/worldsrv/tournament.go
+++ b/worldsrv/tournament.go
@@ -959,7 +959,7 @@ func (this *Tournament) NextRoundStartSingle(sortId int64, playerCtx *PlayerMatc
 		}
 
 		if promotionNum != 1 {
-			arr = append(arr[:promotionNum])
+			arr = arr[:promotionNum]
 			playerCtx.tm.robotGrades[int(round)] = arr
 		}