diff --git a/install.sh b/install.sh
index 35a13e6..ff1bfaf 100755
--- a/install.sh
+++ b/install.sh
@@ -240,7 +240,7 @@ nvm_do_install() {
     printf "$SOURCE_STR"
     echo
   else
-    if ! command grep -qc '/nvm.sh' "$NVM_PROFILE"; then
+    if ! `grep -qc '/nvm.sh' "$NVM_PROFILE"`; then
       echo "=> Appending source string to $NVM_PROFILE"
       printf "$SOURCE_STR\n" >> "$NVM_PROFILE"
     else