diff --git a/components/esptool_py/flasher_args.json.in b/components/esptool_py/flasher_args.json.in
index 6b72fc9bf..2152d6877 100644
--- a/components/esptool_py/flasher_args.json.in
+++ b/components/esptool_py/flasher_args.json.in
@@ -12,7 +12,7 @@
         >
     },
     $<JOIN:$<TARGET_PROPERTY:flash,FLASH_ENTRY>,,
-    >,
+    >$<$<BOOL:$<TARGET_PROPERTY:flash,FLASH_ENTRY>>:,>
     "extra_esptool_args" : {
         "after"  : "${ESPTOOLPY_AFTER}",
         "before" : "${ESPTOOLPY_BEFORE}",