Adelaide Strikers remain in the hunt to claim a second Big Bash League title after upsetting defending champions Perth Scorchers by 50 runs in a knockout final on Saturday, courtesy of an enterprising half-century by Jake Weatherald.

In front of a Perth Stadium crowd undeterred by the departure of a slew of players to foreign Twenty20 leagues, the visitors overcame a sluggish start to post 155-7 from 20 overs before bowling out the Scorchers for 105.

The Strikers now head to the Gold Coast for Monday's clash with Brisbane Heat, with the winner playing Sydney Sixers in Wednesday's grand final at the Sydney Cricket Ground.

"This was awesome tonight, I love batting here. It's just come off, other times it won't, but it's just good fun," Weatherald told Fox Cricket after blasting 56 off 32 balls.

On debut, opener Sam Fanning endeared himself to locals with two monstrous sixes in a brisk 31 but the wheels quickly fell off for the Scorchers, who were undone by spin as regular wickets halted their run-chase.

Strikers captain Matthew Short (1-31) held on to a stunning one-handed diving catch off his own bowling to dismiss Nick Hobson (4) and expose the tail, which was mopped up by spinners Lloyd Pope (4-24) and Cameron Boyce (3-20).

The Scorchers season, and the prospect of a third straight title, came to an end after 16.2 overs when Boyce had Cooper Connolly (31) caught by James Bazley, juggling on the boundary rope at long-on.Bowling first had paid early dividends for Aaron Hardie (2-24) with Short, the season's top run-scorer, bowled for 13 by a hooping Andrew Tye inswinger as the Strikers slumped to 52-4 in their first 10 overs.

Targeting the left-arm spin of Ashton Agar, Weatherald fired back with eight fours and two sixes, setting the stage for Henry Thornton (28 not out) and Ben Manenti (23) who ensured the visitors produced a winning score.