Western Australia 355 and 3 for 115 (Short 56*) lead South Australia 201 (McInerney 51, Guthrie 4-59) by 269 runs
Four wickets to 20-year-old left arm paceman Liam Guthrie put Western Australia in command of the Sheffield Shield clash with South Australia at Glenelg Oval.
Guthrie tore through the Redbacks top order, taking four of the first six wickets as the hosts stumbled to 6 for 120.
Opener Conor McInerney, playing just his second match, provided the only real resistance with 51. The rest of the side fell away to be all out 154 runs behind on the first innings.
The Redbacks made a bright start with the ball to leave the Warriors 3 for 30 in their second innings before D'Arcy Short and Ashton Turner steadied with an unbeaten 85-run stand.