diff --git a/src/OCE/IOM/iom.F90 b/src/OCE/IOM/iom.F90
index dbccf2c752325b3b2b2c5e95aa26954fe8ef0ca0..f6ac95b9274941401aabc032ec7056627736b1f9 100644
--- a/src/OCE/IOM/iom.F90
+++ b/src/OCE/IOM/iom.F90
@@ -751,7 +751,7 @@ CONTAINS
       ! =============
       clname   = trim(cdname)
       IF ( .NOT. Agrif_Root() .AND. .NOT. lliof ) THEN
-         iln    = INDEX(clname,'/')
+         iln    = INDEX(clname,'/', BACK=.TRUE.)
          cltmpn = clname(1:iln)
          clname = clname(iln+1:LEN_TRIM(clname))
          clname=TRIM(cltmpn)//TRIM(Agrif_CFixed())//'_'//TRIM(clname)