Marcus Harris has posted his highest score this Sheffield Shield season, helping Western Australia to 3-181 at tea on day one of the final against Victoria.

The Warriors resumed after lunch on 0-84, with Harris (81) putting his foot down to reach his half century soon after.

However, a 130-run partnership with fellow opener Cameron Bancroft (55) was broken when the latter was caught behind off the bowling of former Test quick Peter Siddle (1-12).

And just as new batsman Michael Klinger (18) was starting to settle, Harris was gone, bowled by a Fawad Ahmed (2-43) spinner that swept around leg side to rattle the stumps.

Klinger didn’t last long, the second victim of Ahmed, caught behind as WA lost three wickets for 33 runs.

Shaun Marsh (five not out) and WA skipper Adam Voges (18 not out) will aim to steady the ship.

Western Australia need an outright victory in the five-day final to secure the Shield, while Victoria will get the prize with a draw.