diff --git a/pam_yubico.8 b/pam_yubico.8
index a75f03a..e484440 100644
--- a/pam_yubico.8
+++ b/pam_yubico.8
@@ -43,7 +43,7 @@ The module is for authentication of YubiKeys, either with online validation of O
 Turns on debugging to STDOUT
 .TP
 .B mode=\fR[\fIclient\fR|\fIchallenge-response\fR]
-Set the mode of operation, client for OTP validation and challenge-response for challenge-response validation.
+Set the mode of operation, client for OTP validation and challenge-response for challenge-response validation, client is the default.
 .TP
 .B authfile=\fIfile\fR
 Set the location of the file that holds the mappings of Yubikey token IDs to user names.