diff --git a/check_pg_streaming_replication b/check_pg_streaming_replication
index 99369e6..c314677 100755
--- a/check_pg_streaming_replication
+++ b/check_pg_streaming_replication
@@ -149,7 +149,7 @@ fi
 debug "Postgres is running"
 
 RECOVERY_MODE=0
-[ $( psql_get 'SELECT pg_is_in_recovery();' ) == "t" ] && RECOVERY_MODE=1
+[ "$( psql_get 'SELECT pg_is_in_recovery();' )" == "t" ] && RECOVERY_MODE=1
 
 if [ -f $RECOVERY_CONF ]
 then