A tape drive may arrange timing-based-servo marks into a timing-based-servo pattern. The timing-based-servo pattern may be at least one M-pattern. The tape drive may select the at least one M-pattern. The tape drive may match at least two timing-based-servo marks in the at least one M-pattern. The tape drive may determine, from the matching, whether an alignment of the at least two timing-based-servo marks is demonstrative of tape-creep.