@@ -883,13 +883,13 @@ gstring_middle[expr_ty]:
 # TODO: (Ideally we need a way similar to 'memo' so the parser can set the tokenize mode on fstring/normal)
 gstring_replacement_field[expr_ty]:
     | expr_start='{' a=(yield_expr | star_expressions) debug_expr="="? conversion=[
-        "!" conv=NAME {conv}
+        conv_token="!" conv=NAME { _PyPegen_check_fstring_conversion(p, conv_token, conv) ? NULL : conv }
     ] format=[
         ':' spec=gstring_format_spec* { spec ? _PyAST_JoinedStr((asdl_expr_seq*)spec, EXTRA) : NULL }
     ] &&'}' {
         _PyPegen_formatted_value(p, a, debug_expr, conversion, format, EXTRA)
     }
-gstring_format_spec[expr_ty]: 
+gstring_format_spec[expr_ty]:
     | t=FSTRING_MIDDLE { _PyPegen_constant_from_token2(p, t) }
     | gstring_replacement_field
 gstring[expr_ty]:
 
@@ -1071,6 +1071,19 @@ _PyPegen_check_legacy_stmt(Parser *p, expr_ty name) {
     return 0;
 }
 
+int
+_PyPegen_check_fstring_conversion(Parser *p, Token* symbol, expr_ty conv) {
+    if (symbol->lineno != conv->lineno || symbol->end_col_offset != conv->col_offset) {
+        RAISE_SYNTAX_ERROR_KNOWN_RANGE(
+            symbol, conv,
+            "conversion type must come right after the exclamanation mark"
+        );
+        return 1;
+    }
+    return 0;
+}
+
+
 const char *
 _PyPegen_get_expr_name(expr_ty e)
 {
 
@@ -329,6 +329,7 @@ expr_ty _PyPegen_ensure_real(Parser *p, expr_ty);
 asdl_seq *_PyPegen_join_sequences(Parser *, asdl_seq *, asdl_seq *);
 int _PyPegen_check_barry_as_flufl(Parser *, Token *);
 int _PyPegen_check_legacy_stmt(Parser *p, expr_ty t);
+int _PyPegen_check_fstring_conversion(Parser *p, Token *, expr_ty t);
 mod_ty _PyPegen_make_module(Parser *, asdl_stmt_seq *);
 void *_PyPegen_arguments_parsing_error(Parser *, expr_ty);
 expr_ty _PyPegen_get_last_comprehension_item(comprehension_ty comprehension);