[Bob Proctor]

If the clock is started on the ready and runs out after an accepted foul, you must have an untimed down.

Rule ref. 3.3.3a: "A period must be extended by an untimed down if during the last timed down of the period, one of the following occurs: (a) There was a foul, other than unsportsmanlike or non-player, by either team and the penalty is accepted".