Jonathan Sexton and Leigh Halfpenny scored tries as the unbeaten British and Irish Lions took a 23-10 half-time lead against NSW Warathas during an exciting opening 40 minutes at Allianz Stadium.
Ireland fly-half Sexton pounced after just six minutes, while full-back Halfpenny slotted the conversion and three penalties to keep the Waratahs at bay before grabbing his own try on the stroke of half-time.
The home side, despite being without several players at the Australia training camp ahead of next weekend's first Test in Brisbane, conjured a breakaway try for centre Tom Carter, with scrum-half Brendan McKibbin converting and booting a penalty.
The Lions made a blistering start, moving 10-0 ahead after just six minutes - and it could have been even more. Wing Simon Zebo thought he had scored with his first touch of the ball in a Lions shirt after 40 seconds, but Waratahs full-back Drew Mitchell completed a superb try-saving tackle.
Halfpenny, though, kicked a 50-metre penalty three minutes later, before superb approach work from the Wales full-back, Zebo and centre Jonathan Davies created an opening for Sexton that he finished emphatically.
Halfpenny landed the touchline conversion, leaving the Waratahs with an early mountain to climb as they faced a Lions side that had moved up a gear in terms of intensity.
Sexton then took a huge tackle from Waratahs lock Will Skelton, and as he was receiving treatment the Lions conceded a soft try, with Carter being freed in space and capitalising on some weak defensive work.
McKibbin added the extras from wide out before another successful Halfpenny penalty ended a fast and furious opening quarter with the Lions 13-7 in front.
The game was of a similar pace to last Saturday's clash against Queensland Reds, but the Lions looked more composed under pressure than seven days ago, and another Halfpenny penalty extended their advantage to nine points.
McKibbin then found his range from 45 metres, though, before Halfpenny converted his own try and the Lions trooped off well ahead.