diff --git a/completion/available/pip.completion.bash b/completion/available/pip.completion.bash
index 618909ad..df790073 100644
--- a/completion/available/pip.completion.bash
+++ b/completion/available/pip.completion.bash
@@ -5,6 +5,6 @@
 # If the pip package is installed within virtual environments, say, python managed by pyenv,
 # you should first initilization the corresponding environment.
 # So that the pip/pip3 is in system's path.
-if command -v pip >/dev/null; then
-  eval "$(pip completion --bash)"
+if _command_exists pip; then
+    eval "$(pip completion --bash)"
 fi
diff --git a/completion/available/pip3.completion.bash b/completion/available/pip3.completion.bash
index 1e2ffb42..7662f2e8 100644
--- a/completion/available/pip3.completion.bash
+++ b/completion/available/pip3.completion.bash
@@ -5,6 +5,6 @@
 # If the pip package is installed within virtual environments, say, python managed by pyenv,
 # you should first initilization the corresponding environment.
 # So that the pip/pip3 is in system's path.
-if command -v pip3 >/dev/null; then
-  eval "$(pip3 completion --bash)"
+if _command_exists pip3; then
+    eval "$(pip3 completion --bash)"
 fi
diff --git a/completion/available/pipenv.completion.bash b/completion/available/pipenv.completion.bash
index 339509f2..1787fed0 100644
--- a/completion/available/pipenv.completion.bash
+++ b/completion/available/pipenv.completion.bash
@@ -1 +1,4 @@
-[[ -x "$(which pipenv)" ]] && eval "$(pipenv --completion)"
+if _command_exists pipenv
+then
+    eval "$(pipenv --completion)"
+fi