Sydney Thunder are in prime position to hand Perth their first loss of the Big Bash League season after posting a strong 7-200 at Manuka Oval.
Twin half-centuries for Sam Billings and Jason Sangha saw the duo add 113 runs for the third wicket after the Thunder were sent in to bat.
Returning Scorcher quick Matthew Kelly picked up the early wickets of Matthew Gilkes and Alex Hales to leave Sydney 2-23, but it was only for a rare moment that Perth were on top.
Billings drove beautifully for four off his first ball and quickly pulled another boundary, but an elegant back-foot cut to Ashton Agar's spin confirmed the Englishman was on song.
Sangha eased into his innings but cracked back-to-back fours on the leg side to ramp things up, while the in-form Billings took Mitch Marsh for his own consecutive boundaries as the Thunder raced to 2-83 at the halfway mark.
The Scorchers subbed in X-factor player Lance Morris at the expense of spinner Peter Hatzoglou but his pace did little to stop the Thunder's roll, Billings twice flicking him for four through mid-wicket in his first over as his side passed the 100 mark in the 12th over.
Billings marked his 50 with a highlight-reel six, depositing a Marsh delivery onto the roof of the Bob Hawke Stand to reach his half-century in 27 balls.
Danger quick AJ Tye finally spoilt the party, finding an edge to dismiss the lethal Billings for 67 off 35 balls and make the score 3-136.
But Tye, the competition's leading wicket-taker, bowled two dangerous above waist-high no balls in his next three deliveries to Alex Ross and was taken out of the attack by the umpires mid-over.
Sangha brought up his 50 off 42 balls and finished unbeaten on 56, while Chris Green's cameo 14 not out helped Sydney reach 200 from their final delivery.
Kelly finished with 3-30 for the Scorchers.
