diff --git a/fmt/format.h b/fmt/format.h
index 7385b76980a2..29927823687c 100644
--- a/fmt/format.h
+++ b/fmt/format.h
@@ -1153,7 +1153,9 @@ struct ConvertToIntImpl2<T, true> {
 
 template<typename T>
 struct ConvertToInt {
-  enum { enable_conversion = sizeof(convert(get<T>())) == sizeof(Yes) };
+  enum {
+    enable_conversion = sizeof(fmt::internal::convert(get<T>())) == sizeof(Yes)
+  };
   enum { value = ConvertToIntImpl2<T, enable_conversion>::value };
 };
 
diff --git a/test/format-test.cc b/test/format-test.cc
index a3eb907e8505..e8037dcac7b1 100644
--- a/test/format-test.cc
+++ b/test/format-test.cc
@@ -1653,3 +1653,11 @@ FMT_VARIADIC(void, custom_format, const char *)
 TEST(FormatTest, CustomArgFormatter) {
   custom_format("{}", 42);
 }
+
+void convert(int);
+
+// Check if there is no collision with convert function in the global namespace.
+TEST(FormatTest, ConvertCollision) {
+  fmt::format("{}", 42);
+}
+