Peter Siddle celebrated his birthday with a stunning hat-trick to kick-start Australia's Ashes campaign at the Gabba and hand England a miserable opening day to the series. Alastair Cook appeared to be steering the tourists into a favourable position until Siddle, returning to Test cricket after a spell out with a stress fracture of the back, marked his 26th birthday in memorable fashion. The Victorian became the 11th Australian to take a Test match hat-trick when he had Cook edging to slip for 67, via front-foot defence, then had too much pace for both Matt Prior and Stuart Broad to leave England struggling on 197 for seven. Ian Bell did his best to lift England to a competitive total with a classy 76, but the tourists were eventually dismissed for 260, with Siddle boasting figures of six for 54. England's day had begun alarmingly when captain Andrew Strauss fell for a third-ball duck in the first over after choosing to bat first. But on a pitch tinged with green and playing a little slower than anticipated, Cook responded with a 127-ball half-century which contained just four fours, rarely excited but was a highly valuable contribution. England were thankful for his diligence - and for the fallibility of debutant Xavier Doherty, who put down a routine chance at point from a tame cut at Shane Watson to reprieve Cook on 26. Strauss thought he saw a scoring opportunity off the third ball from Ben Hilfenhaus, only for a hint of movement back into him from an otherwise innocuous short ball to result in a cut straight into the hands of gully fielder Mike Hussey. There was another scare for England when Australia chanced a review for lbw against number three Jonathan Trott. They lost it, though, with Aleem Dar's not-out verdict standing after simulation suggested the ball from Siddle was clipping only the outside of leg stump. Trott was to go straight after morning drinks anyway, from the last ball of Watson's first over, driving round a full-length delivery to be bowled off and middle stump. It was time for Kevin Pietersen, and he seemed at ease with his task either side of lunch - providing several glimpses, in a 70-ball stay, of his mercurial best. Sadly, to English eyes, he did not stay long enough - pushing out at an attempted drive on the up and being caught high at second slip for 43 by Ricky Ponting when late movement brought the edge and ended a stand of 76 at the start of a new spell from Siddle. A minor variation of Pietersen's dismissal soon accounted for Paul Collingwood. Siddle had floated up a half-volley to get Collingwood off the mark with an on-driven four, but two balls later it was all over for the new batsman - edging low to third slip. Despite Cook's determination, England were still looking for a partnership which might define the innings. In-form batsman Bell was the next big hope, and under increasing cloud cover he served his team well. Australia were out of DRS chances by then too, having queried Dar again to no avail when Johnson wrongly thought he had Bell edging behind on 18. Australia set out to test England's patience after tea, but Cook and Bell mostly ignored the wide lines and played the waiting game. The balance of power was marginally with England until Siddle got one in the perfect spot to finally see off Cook, then clean-bowled Prior - attempting an ambitious drive first ball - and had Broad lbw with a yorker. England tried DRS as a last resort. Not even that could stop the celebrations of a partisan sell-out crowd, but soon afterwards Bell reached a deserved half-century from 103 balls. While the Warwickshire man remained, though, Graeme Swann was quickly making the walk back. Siddle continued his momentum with a straight one which Swann (10) tried to play around his front leg only to be trapped leg before. James Anderson escaped when he was dropped by Brad Haddin off another Siddle delivery while still without a run. But before the day was out, the key scalp of Bell (76) fell when he hit a Doherty delivery to deep cover for Shane Watson to make the catch. The tourists were all out for when Doherty followed Bell's dismissal by seeing off Anderson (11). In reply, Australia reached 25-0 with Simon Katich and Shane Watson untroubled by Broad, Anderson and a single over from Graeme Swann.