diff --git a/spring-data-redis/src/main/java/org/springframework/data/keyvalue/redis/util/DefaultRedisSet.java b/spring-data-redis/src/main/java/org/springframework/data/keyvalue/redis/util/DefaultRedisSet.java
index 9e85f062f..af7d86741 100644
--- a/spring-data-redis/src/main/java/org/springframework/data/keyvalue/redis/util/DefaultRedisSet.java
+++ b/spring-data-redis/src/main/java/org/springframework/data/keyvalue/redis/util/DefaultRedisSet.java
@@ -129,7 +129,7 @@ public class DefaultRedisSet<E> extends AbstractRedisCollection<E> implements Re
 	}
 
 	private String[] extractKeys(RedisSet<?>... sets) {
-		String[] keys = new String[sets.length + 1];
+		String[] keys = new String[sets.length];
 		for (int i = 0; i < keys.length; i++) {
 			keys[i] = sets[i].getKey();
 		}