diff --git a/mrbgems/mruby-proc-ext/src/proc.c b/mrbgems/mruby-proc-ext/src/proc.c
index ac4b08f9d..0ef754410 100644
--- a/mrbgems/mruby-proc-ext/src/proc.c
+++ b/mrbgems/mruby-proc-ext/src/proc.c
@@ -182,8 +182,7 @@ mrb_mruby_proc_ext_gem_init(mrb_state* mrb)
   mrb_define_method(mrb, p, "inspect",         proc_inspect,         MRB_ARGS_NONE());
   mrb_define_method(mrb, p, "parameters",      mrb_proc_parameters,  MRB_ARGS_NONE());
 
-  mrb_define_class_method(mrb, mrb->kernel_module, "proc", kernel_proc, MRB_ARGS_NONE()|MRB_ARGS_BLOCK());
-  mrb_define_method(mrb, mrb->kernel_module,       "proc", kernel_proc, MRB_ARGS_NONE()|MRB_ARGS_BLOCK());
+  mrb_define_method(mrb, mrb->kernel_module,   "proc", kernel_proc,  MRB_ARGS_NONE()|MRB_ARGS_BLOCK());
 }
 
 void