diff --git a/libsrc/cbm/sysrename.s b/libsrc/cbm/sysrename.s
index b4211f9b4..4b299d250 100644
--- a/libsrc/cbm/sysrename.s
+++ b/libsrc/cbm/sysrename.s
@@ -7,7 +7,7 @@
         .export         __sysrename
 
         .import         fnparse, fnadd, fnparsename
-        .import         writefndiskcmd, closecmdchannel
+        .import         opencmdchannel, closecmdchannel, writefndiskcmd
         .import         popax
 
         .import         fncmd, fnunit
@@ -28,6 +28,10 @@
         jsr     fnparsename     ; Parse second filename
         bne     done
 
+        ldx     fnunit
+        jsr     opencmdchannel
+        bne     done
+
         lda     #'r'            ; Rename command
         sta     fncmd
         jsr     writefndiskcmd