diff --git a/modules/caddyhttp/reverseproxy/healthchecks.go b/modules/caddyhttp/reverseproxy/healthchecks.go
index 982c1ec39bd..705afd78fef 100644
--- a/modules/caddyhttp/reverseproxy/healthchecks.go
+++ b/modules/caddyhttp/reverseproxy/healthchecks.go
@@ -133,7 +133,7 @@ type ActiveHealthChecks struct {
 	// body of a healthy backend.
 	ExpectBody string `json:"expect_body,omitempty"`
 
-	transport http.RoundTripper `json:"transport,omitempty"`
+	transport http.RoundTripper `json:"-"``
 	uri        *url.URL
 	httpClient *http.Client
 	bodyRegexp *regexp.Regexp