The 10-point loss was Cronulla's 33rd defeat from 39 matches at the venue, easily their worst record at any ground in the NRL.
The Trbojevic brothers were outstanding for Manly, both crossing for a try in a game that will help new coach Trent Barrett sleep well tonight.
Tom ran for 196 metres in his first game on the wing in 2016, while Jake was rock-solid in defence, racking up 45 tackles.