diff --git a/authentication_sasl_continue.go b/authentication_sasl_continue.go
index a393ae10..1b918a6e 100644
--- a/authentication_sasl_continue.go
+++ b/authentication_sasl_continue.go
@@ -40,7 +40,6 @@ func (src *AuthenticationSASLContinue) Encode(dst []byte) []byte {
 	dst = pgio.AppendInt32(dst, -1)
 	dst = pgio.AppendUint32(dst, AuthTypeSASLContinue)
 
-	dst = pgio.AppendInt32(dst, int32(len(src.Data)))
 	dst = append(dst, src.Data...)
 
 	pgio.SetInt32(dst[sp:], int32(len(dst[sp:])))
diff --git a/authentication_sasl_final.go b/authentication_sasl_final.go
index b8f89d59..11d35660 100644
--- a/authentication_sasl_final.go
+++ b/authentication_sasl_final.go
@@ -40,7 +40,6 @@ func (src *AuthenticationSASLFinal) Encode(dst []byte) []byte {
 	dst = pgio.AppendInt32(dst, -1)
 	dst = pgio.AppendUint32(dst, AuthTypeSASLFinal)
 
-	dst = pgio.AppendInt32(dst, int32(len(src.Data)))
 	dst = append(dst, src.Data...)
 
 	pgio.SetInt32(dst[sp:], int32(len(dst[sp:])))