Kidderminster weathered a late Peterborough storm to earn themselves a replay with a 0-0 draw at Aggborough, ensuring they will be in the draw for the fourth round.
A late scramble - after Lee Tomlin's free-kick struck the crossbar - saw the woodwork hit three times in quick succession but the Skrill Premier side clung on for a draw.
Harriers flew out of the traps and almost took the lead with just a minute on the clock as Joe Lolley's shot hit the crossbar via a hefty deflection.
Tomlin had the first sight of goal for the visitors but fired over when well placed just inside the penalty area.
Lolley was at the heart of everything good about Kidderminster's play.
On the half-hour mark the youngster once again cut in off the wing and unleashed a low shot that Posh shot-stopper Bobby Olejnik did well to keep out.
The visitors finished the half on the front foot, however, as Tomlin saw his free-kick smartly saved by Dan Lewis.
Shaun Jeffers had a great chance to break the deadlock minutes after the restart but his point-blank header was brilliantly tipped over by Lewis.
Lee Vaughan then burst through a static defence for the hosts but sliced his shot high and wide when one-on-one with the onrushing Olejnik.
The defender soon made amends, though, clearing off the line after Britt Assombalonga had flicked the ball over Lewis.
Assombalonga reacted fastest to a ball into the box minutes later but Lewis was equal to his close-range header.
Tomlin's free-kick then rattled the crossbar before the follow-up was cleared off the line following a chaotic scramble as Kidderminster held on.