South Australia 251 & 268 (Nielsen 82, Cooper 49, Kelly 5-61) lead Western Australia 207 & 4 for 146 (S Marsh 72*, M Marsh 44, Worrall 3-58) by 166 runs
A fluent unbeaten half-century from Shaun Marsh has given Western Australia a chance at chasing a big fourth innings total of 313 against South Australia at Adelaide Oval.
Marsh and his younger brother Mitchell steadied with an 83-run stand for the third wicket on day three after the chase started with the early loss of Josh Philippe and Hilton Cartwright.
Philippe was adjudged lbw to Daniel Worrall for 6, despite possibly getting an inside edge. Cartwright edged a half volley from Nick Winter to leave Western Australia 2 for 24.
But the Marsh brothers took control. Shaun Marsh continued his form cruising to 72 not out following his century in the third ODI against South Africa.
Mitchell Marsh was eventually undone on 44, bowled through the gate by an off cutter from Worrall. Ashton Turner became Worrall's 10th victim of the match four balls later. Shaun Marsh and Will Bosisto made it through to stumps, WA still needing 167 to win with six wickets in hand.
Earlier, Redbacks wicketkeeper Harry Nielsen made a vital 82 to help the home side set a fourth innings chase of over 300. It was Nielsen's second score in excess of 50 in Sheffield Shield after making a century on debut last summer.
He was ably supported by Tom Cooper (49) and Nick Winter (38). Warriors pacer Matt Kelly picked up the last two wickets of the innings, including Nielsen, to finish with 5 for 61.