Simon Katich scored his maiden Ashes hundred and Australia captain Ricky Ponting also reached three figures to keep England at bay on the second day of the first Ashes Test at Cardiff on Thursday.
Australia, at stumps at Sophia Gardens, were 249 for one in reply to England's first innings 435, a deficit of 186.
Left-handed opener Katich, dropped early in his innings, was 104 not out and Ponting 100 not out, with their unbroken stand worth 189.
Katich, who has been at the crease for nearly five hours, became the first cricketer to score a Test hundred in Wales when he pulled Andrew Flintoff to post his eighth century at this level off 214 balls with eight fours.
Ponting, who by contrast was compiling his 38th Test hundred, followed him to the landmark with a single off the penultimate ball of the day, also from Flintoff, to bring up a century in 155 balls with eight fours.
During the course of his innings Ponting joined Sachin Tendulkar, Brian Lara and former Australia captain Allan Border as the only batsmen to have made more than 11,000 Test runs.
A still largely docile pitch was as much of a stumbling block to England's attack as it had been to their Australian counterparts and highlighted the lack of truly fearsome fast bowlers on either side.
The one exception was Flintoff, who produced a ferocious burst when introduced into the attack after lunch that saw him remove opener and Ashes debutant Phillip Hughes.
Flintoff immediately tested the 20-year-old left-hander from around the wicket in a bid to cramp the batsman for room.
The pace bowler then saw Katich, on 10, drive the ball low and hard back at him only for Flintoff, in his follow through, to drop the difficult caught and bowled chance.
Hughes, who favours the offside, had made 28 runs off 30 balls before lunch.
But it was a different story after the break with the 20-year-old only managing eight off 24 in the face of some fiery bowling from Flintoff, playing his first Test of the season following a knee injury.
Hughes was eventually out for 36 when he inside edged Flintoff, the hero of England's 2005 Ashes series win, and wicket-keeper Matt Prior held a good, low diving catch.
But that was as good as it got for England in the session, even though Flintoff, who took one wicket for 15 runs in six overs, several times beat Katich on the outside edge
Off-spinner Graeme Swann reeled off five consecutive maidens on a pitch taking turn but Australia's second-wicket duo were rarely troubled by him or left-arm spinner Monty Panesar.
However, Swann was convinced he had Katich lbw for 56 with a ball that pitched in line and spun past the batsman's defences.
But West Indian umpire Billy Doctrove was unmoved.
Ponting produced a chanceless display, driving and pulling in typically authoritative fashion as he scored his eighth Test century against England.
Swann had had more success earlier in the day with the bat.
Coming in at No 9, he made 47 not out and, together with James Anderson (26), had shared in a valuable ninth-wicket stand of 68 in just 53 balls before lunch.
Swann struck rival off-spinner Nathan Hauritz for three fours in a row, the last a cheeky reverse sweep that took England past 400 after they'd resumed on 336 for seven with all of their specialist batsmen out.
But he was left just short of his second Test fifty when last man Panesar edged Hauritz to Ponting in the slips.