diff --git a/security/openssl/3.1/Makefile b/security/openssl/3.1/Makefile
index 6c58d2c5d5f..b603c8c36aa 100644
--- a/security/openssl/3.1/Makefile
+++ b/security/openssl/3.1/Makefile
@@ -31,7 +31,7 @@ CONFIGURE_ARGS+=	no-asm
 
 INSTALL_TARGET=		install_sw install_ssldirs install_man_docs
 
-SUBST_VARS+=		MAN_PREFIX SHLIBVER
+SUBST_VARS+=		SHLIBVER
 
 # install to unusual directory name - this port is *not* intended to be
 # picked up by configure scripts without explicitly CPPFLAGS/LDFLAGS.