To that point, Cowan's main involvement of the day had been to watch the Sri Lankan attack get dominated by Warner, who hammered his first 30 runs off 19 deliveries while Cowan was stuck on one.
Cowan was run out soon after, paying the price for hesitating when turning for a second run, giving Nuwan Pradeep more than enough time to have the 30-year-old well short of his ground.
Departing skipper Mahela Jayawardene seemed to have no answers as he rotated his second-string pace attack - clearly missing injured trio Nuwan Kulasekara, Chanaka Welegedara and Shaminda Eranga.
Newcomers Nuwan Pradeep (0-39), Suranga Lakmal (0-37) and Dhammika Prasad (0-21) all felt Warner's wrath as he cracked his 50 off just 37 deliveries, eyed off a fourth Test century and passed a personal milestone.
Rocking on to his heels, Warner smashed a cut shot just wide of point to race past 1000 Test runs.
Warner, a swashbuckling left-hander whose place in the team has always been under some pressure, reached the mark in his 25th innings.
He notched the milestone faster than Test captain Clarke (26 innings), Australia's two greatest batsman after Don Bradman - Chappell (26) and Ponting (27) - and power-hitting pair Adam Gilchrist (26) and Matt Hayden (27).
Hughes continued his impressive return to Test cricket, building on the 86 scored in the first Test at Bellerive.
Showing off his rebuilt game, the 24-year-old mixed his trademark slashes outside off stump with mighty pull shots to bring up his half century just before the break.
- AAP