Western Australia 191 (Short 51) and 3 for 28 need 324 more runs to beat New South Wales 8 for 444 dec

Pat Cummins produced a display that showed he was in prime shape for the Test season. in the process putting New South Wales on track to make it four Sheffield Shield wins in a row with Western Australia facing a final-day battle to save the game at the SCG with just seven wickets in hand.

Cummins, in his first first-class outing since the Ashes, produced an eye-catching spell of reverse swing during the morning session to take out the WA middle order - which was followed by another super spell from Mitchell Starc before stumps - while Nathan Lyon and Steve O'Keefe combined for five wickets as New South Wales showed tremendous skill on a slow surface.

"The wicket is just so dry and hard, super abrasive, after about 30 overs the ball looked like it was 100 overs old, so it's reversing pretty early," Cummins said. "It's the first time I've bowled with a reversing ball for probably 12 months so was just trying to attack the pegs, get it swinging a bit each way, and fortunately today there were a few nicks and they carried which doesn't always happen when the ball is reversing."

WA slumped from 1 for 116 to 191 all out in their first innings but Peter Nevill opted to extend the lead rather than bowl again. Moises Henriques was promoted to open and biffed an unbroken opening stand of 98 with Daniel Hughes, who helped himself to a half-century.

Armed with the new ball, Cummins then struck early when Josh Philippe was bowled round his legs for the second time in the match - this time by the right-armer from over the wicket, compared to Starc in the first. With three overs left in the day, Starc then pinned Shaun Marsh lbw with a delivery that tailed back, meaning Marsh had been dismissed twice in the day, and then speared one through nightwatchman Matt Kelly as Western Australia stumbled to the close.

After the dramatic collapse of Australia A the previous day in Perth, Marsh had the chance to make things more awkward for the selectors with a big score when play resumed against the possible Test attack, but he chipped limply to mid-on for 43. From there, the innings unraveled. D'Arcy Short had played against his natural instincts to register a 154-ball fifty before falling two overs after Marsh when he missed a very full delivery from O'Keefe.

Cummins then set to work as he found just enough movement to challenge both edges of the bat. Ashton Turner nicked behind, Cameron Green shouldered arms to one which came back to take off stump, and Josh Inglis edged to slip in the final over before lunch.

There was some resistance after the break as Marcus Stoinis and Ashton Agar stayed together for 20 overs, but scoring was mighty difficult. Stoinis appeared to get a rough decision when he was given caught at slip when replays suggested he played over the top of the delivery from Lyon, the offspinner then bowling Kelly for a duck three balls later.

Andrew McGlashan is a deputy editor at ESPNcricinfo