De Pasquale was consistently quick across the half-hour session, setting the early pace with a 1m30.695s.
With 11 minutes to go Shane van Gisbergen had his first crack on a green tyre for the weekend, the Kiwi rocketing to first with a 1m30.095s.
De Pasquale responded with a green tyre run of his own, pipping van Gisbergen’s time by seven-hundredths.
Brown then dipped into the 1m29s for the first time in the session with a 1m29.953s, only to be edged by a final De Pasquale, the margin between the two a tenth of a second.
Those final laps came right as rain started to fall at the Eastern Creek circuit.