Sydney Sixers tweaker Stephen O'Keefe had the best night of his Twenty20 career to restrict the Sydney Thunder to 6-166 in their top-of-the-table Big Bash clash.
After Alex Hales blitzed his way to a 29-ball half-century for the Thunder in Canberra, O'Keefe spun the Sixers back into the match with his 3-15.
The former Test spinner claimed the key scalps of Hales and Sam Billings in the space of three balls, turning the game on its head.
The figures were the best of his 94-game Twenty20 career and came during a season in which O'Keefe is playing only the BBL after losing his state contract.
His dismissals of Billings and Hales - both caught on the boundary - prompted a five-over block of 3-21.
O'Keefe also removed Alex Ross lbw when he tried to sweep, with fellow spinner Lloyd Pope also taking 1-31 with a beautiful leg break to get Callum Ferguson.
Meanwhile Hales' 54 from just 33 balls took him to the top of the run-scoring charts, after recording back-to-back golden ducks early in the tournament.
More impressively, the Englishman's 323 runs have come at a strike-rate of 163.13, the highest of anyone with more than 200 runs.
Daniel Sams returned from concussion and was the only other Thunder player to fire with his unbeaten 50 from 37 helping his team post a competitive score.
The Sixers lead the Big Bash on 25 points, but a win for the second-placed Thunder will be enough to take them to the top of the competition.