diff --git a/schemars_derive/src/schema_exprs.rs b/schemars_derive/src/schema_exprs.rs
index 1f5df99..3278e99 100644
--- a/schemars_derive/src/schema_exprs.rs
+++ b/schemars_derive/src/schema_exprs.rs
@@ -556,7 +556,7 @@ fn field_default_expr(field: &Field, container_has_default: bool) -> Option<Toke
 
                 impl serde::Serialize for _SchemarsDefaultSerialize<#ty>
                 {
-                    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+                    fn serialize<S>(&self, serializer: S) -> core::result::Result<S::Ok, S::Error>
                     where
                         S: serde::Serializer
                     {