WA secured a rare "three-peat" by crushing Tasmania by 377 runs inside four days at the WACA Ground.

Gannon was the unlucky 12th man for WA's first two titles of the hat-trick.

But injuries to Jhye Richardson, Lance Morris and Matt Kelly meant Gannon became a key figure in WA's bid to secure this season's crown and complete the three-peat.

Gannon saved one of his finest displays for the final, following up his 3-38 in the first innings with 5-23 in the second dig as Tasmania were restricted to totals of 186 and 160.

"It's amazing," Gannon said of the Shield triumph.

"I was in the squad for the last two (finals), I didn't get to go on the field.

"So to actually play and contribute, it's the greatest thing I've done in cricket. It's so good."

Gannon moved from Queensland to WA in 2020, but the Warriors' star-studded bowling line-up meant the 35-year-old has been in and out of the squad over that period.

Despite the intense competition for spots within the WA set-up, Gannon says there hasn't been friction.

"That kind of epitomises our bowling group and our squad as a whole," Gannon said.

"We always talk about how it takes a squad to win these titles.

"It's one of the most selfless bowling groups I've been a part of.

"Generally you're all in the same team but there's a little bit of tension - there's only so many bowling spots.

"Here it feels like everyone is backing each other in.

"When you get your shot, you feel like everyone's behind you, and that's huge from a confidence perspective, and it allows you to go out there and do your job."

The Shield triumph continues a remarkable run of success for the WA men's cricket teams.

The Warriors have now won the past three one-day and Shield crowns, and the Perth Scorchers have won two of the past three BBL titles.

Australian Associated Press