Defending champions Sydney flexed their muscle on Sunday to record back-to-back wins and signal their intention to retain the Kingsgrove Sports Twenty20 Cup.

The Tigers defeated Eastern Suburbs by eight wickets in their morning match before making short work of Manly-Warringah in the second of their double header matches at Drummoyne Oval.

Sydney started the day in fifth spot in the Sydney Sixers Conference but was outright leader by the end of it.

They are well on course to reach the last eight and defend the crown they won last season. Fairfield-Liverpool tops the Sydney Thunder Conference after a big win over Blacktown Mounties.

Sydney's comprehensive victories over two quality sides sent a clear message it is as hungry as ever to add another T20 title to its collection.

Eastern Suburbs never really got going in the first game after electing to bat first.

Nic Bills and Harry Manenti both took three wickets to help restrict the visitors to 9-131 from their 50 overs. The run chase was never in doubt once opener Justin Mosca set about his work.

He blasted six sixes and six fours on his way to an undefeated 85 from just 43 balls.

Mosca's frenetic knock allowed Sydney to ease past the Dolphins in the 15th over for the loss of just two wickets.

It was a similar story in the afternoon match against Manly.

The Waratahs struggled for any real momentum after being sent in, finishing at a modest 7-126 after 20 overs.

That was never going to be enough against this rampant Sydney batting line-up.

The top order all made some sort of contribution as the target was reached three down in the 17th over.

Fairfield-Liverpool was just as ruthless in a one-sided contest against Blacktown.

The Mounties made just 9-118 in reply to the Lions' imposing 7-169.

Riley Allington (3-18) was the pick of the Fairfield-Liverpool bowlers.

Needing two wins in a day to climb into the top four in the Sydney Thunder Conference, Western Suburbs went down to Parramatta before defeating Campbelltown-Camden at Pratten Park.

The Kingsgrove Sports Twenty20 Cup resumes on November 22.

Scores here