Led by a superb unbeaten 66 from GWS Giants star Harry Perryman, Osborne was able to defend its total of 8/137 by a three-run margin.

Osborne recovered superbly from 6/48 after opening bowler Joel Merkel bowled brilliantly, taking 2/9 off eight overs.

Walla lost both openers for nought and then found trouble again at 5/61, before Tom Simmons (34) led a comeback that fell just short at the end.

Walla needed a boundary off the last ball but suffered a run out.

Ed Perryman and Jayden Klemke both took three wickets for Osborne.

Elsewhere, Shannon Terlich notched his second century of the season in the Swampies' huge win at Walbundrie.

Terlich was run out for 100 as he and skipper Greg Schuller (41) added 121 for the opening stand.

Brayden Pantling achieved a season high of 55 no as Henty made 5/236.

Walbundrie was never in the hunt, bowled out for 141. Jack Kotzur (37) and Roy Elliot (30) led the scoring.

Pantling completed a great game taking four wickets as all Henty bowlers found their range in an ideal warm-up ahead of finals.

Rand secured its place in the finals with a thumping 10-wicket win over Culcairn at Rand. The Pigeons bowled Culcairn out for 69 in 24 overs.

Daniel Rooke top-scored with 23, while Blake Lieschke led the wicket takers with 3/13.

In reply, Mark Kreutzberger made 330 and Lieschke was unbeaten on 26.

Holbrook finished its home and away season with a big win at Lockhart, the Brookers finishing in fifth place.

A century stand for the second wicket by Hamish Mackinlay (68) and Hayden Wishart (47) set up the visitors' big total of 9/195.

Jackson Wiedemann and Jordan Harrington took two wickets each as veteran opening bowler Clinton Renner suffered a recurrence of a hamstring injury.

Super bowling from Nick Locke (3/8) and Andrew Mackinlay (3/26) ensured Lockhart never threatened the Holbrook target. Connor Widdup top scored with 31.

Brock Burrum overcame an early batting collapse at 7/96 to recover nicely and post 178 at Burrumbuttock against TRYC.

Mitch Lieschke (40), Robbie Sivell (19) and the evergreen Greg Tallent (16) did a great job in the lower order as the home side was bowled out with five overs left.

Ryan Kirkwood (4/42) and Michael Driscoll (2/35) did the early damage.

TRYC never recovered in the run chase from 5/19, finishing with a respectable 131.

Col Hagen (35 no), Todd Hannam (29) and Driscoll (22) were best for the visitors, while Darcy and Trent I'Anson were the pick of the Saints' bowlers.

Week one of the finals will be a beauty, with top team Osborne up against perennial premier Rand.

Walla will be a warm favourite to beat Holbrook at Walla.

The remaining game should be a classic with arguably the two in-form teams, Henty and Brock Burrum, facing off at Henty.

The three winners plus the highest-ranked loser will progress to the preliminary final matches, with the grand final set for March 13.