Chris Pike at the WACA Ground
South Australia is on the road to outright victory at the WACA Ground at stumps on day three after skittling Western Australia for 189 in its second innings on Wednesday.
The Redbacks are now 1-6 chasing 94 for the win going into the final day.
South Australia opener James Smith couldn't last until stumps and was bowled by Michael Hogan without scoring on the last ball of the day.
Michael Klinger will join Harris to start play on Thursday, with Harris not out on two with 88 needed to win.
It was a great day for the Redbacks.
They began with their first innings score on 5-309 in reply to WA's 284 and Dan Christian's 71 helped them to declare on 9-380 with a lead of 96.
WA's openers again started brightly with Liam Davis and Wes Robinson putting on 69, but when Davis fell for 37 and then Marcus North for four, the signs weren't good for the Warriors.
Davis was out caught at first slip by Harris to give Christian his fifth wicket of the match and skipper North didn't last long when he was trapped in front for four by Jake Haberfield to add to the incumbent Test No.6's disappointing first innings of 29.
Robinson was looking steady moving along to 43 before he was out caught behind off Peter George and left WA 3-104.
It was then 4-105 when 18-year-old Marsh was given out caught behind by Tim Ludeman this time off spinner Aaron O'Brien.
Marsh didn't like the decision, but he was likely also out stumped anyway.
Christian continued his superb match having Luke Pomersbach out for one and Luke Ronchi first ball to be on a hat-trick.
He didn't get it, but WA was 6-111 and then 7-126 when Adam Voges was bowled by Haberfield for 26.
Steve Magoffin and Ashley Noffke then led a rearguard action to save face and avoid a three-day defeat.
Magoffin was dropped twice in the slips, but added 16 before being caught behind by Ludeman off Haberfield.
Brad Knowles also added 16 before Christian clean bowled him and then he did the same the very next ball to Hogan to pick up 5-24.
It is the best figures of his career and just his second five-wicket haul and goes nicely with his 4-63 and 71 in the first innings.
Noffke remained 37 not out for the Warriors who only built a lead of 93.
Earlier, Hogan was the pick of WA's bowlers as he picked up his first career five-wicket haul with 5-83.
Knowles also collected 3-87 while Magoffin and Noffke toiled hard for a combined 57 overs without success.
O'Brien (46) was out in the first over when he became Hogan's first victim of the morning.
He was clean bowled, as was Ludeman (22) and Gary Putland (one) as the 28-year-old paceman claimed his best first-class figures.
Ludeman had an interesting stay at the crease as he was hit in the head twice from bouncers, including one that cut his chin, but the wicketkeeper also hit some nice shots including five boundaries.
Western Australia 1st innings 284
South Australia 1st innings
Smith c Hogan b Knowles 78
Harris b Hogan 0
Klinger b Knowles 74
Borgas b Hogan 39
Cooper c North b Voges 26
O'Brien b Hogan 46
Christian c Ronchi b Knowles 71
Ludeman b Hogan 22
Putland b Hogan 1
Haberfield not out 0
Extras: 23 (9lb, 6nb,