Sydney Thunder 158 for 6 (Knight 50) beat Sydney Sixers 140 (Gardner 49, Bates 3-22) by 18 runs

Key performances from in-form duo Heather Knight and Samantha Bates earned Sydney Thunder the first derby bragging rights of the season over Sydney Sixers with an 18-run win at the SCG.

Knight's fluent 50 off 31 balls, a continuation of the impact she has had this season, led Thunder to a total that appeared around par on a good batting surface and a strong Thunder attack defended it expertly. The result kept Thunder top of the table and strongly placed to push for a home grand final with five games remaining.

Sixers fell to 63 for 5 in the 10th over but Ash Gardner was keeping them in the contest with a timely return to form after her previous four innings in the tournament had brought 24 runs. But with 28 needed off 14 balls she was deceived through the air as she advanced at Bates and with her went the home side's hopes.

Bates took her wicket tally to 11 from the last three games and was back at the top of the season charts ahead of Alana King. Shabnim Ismail, despite being wicketless, also played a key role as she conceded just five an over and was also superb in the outfield with four catches on a blustery afternoon.

With the bat, Chamari Athapaththu, well supported in the crowd by a strong Sri Lanka presence, helped lay a solid base and the acceleration came in the second half of the innings from Knight and Phoebe Litchfield. The pair took 30 without loss off the two power surge overs and though they couldn't stay to close things out Thunder had enough.