With Tiripano surviving more than an hour of hostile bowling and Vusi Sibanda progressing to 38 not out, Zimbabwe's deficit had shrunk to 61 runs when the lunch interval arrived.
The hosts resumed on their overnight total of 28 for one, with Sibanda more than willing to take on the South African attack as Tiripano just looked to cling on.
The nightwatchman was not cowed despite being hit on the back as Dale Steyn delivered a fierce spell of short bowling from around the wicket.
Although Mark Vermeulen looked scratchy early on in his innings and survived both a missed stumping and a good shout for lbw, he reached lunch on 10 not out.