Just two-and-a half-years ago, Australia's quest to regain the Ashes left Ryan Harris at the lowest ebb of his cricket career.

But the injury-hit pace bowler finally put those painful memories on one side as he led Australia's attack on the first day of the second Ashes Test at Lord's on Thursday.

Before lunch Harris took two wickets in five balls, including the prized scalp of Kevin Pietersen, in front of a capacity crowd featuring Queen Elizabeth II, to give Australia renewed hope of regaining the Ashes.

Harris also dismissed Trott later to bag three wickets on day one.