UPDATE 1-Rugby-Australia surge back to beat England 18-9

* Australia fight back with dominant second-half display

* First leg of grand slam in the bag for Wallabies

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By Mitch Phillips

LONDON, Nov 7 (Reuters) - Australia completed the first leg of a potential grand slam when they produced a dominant second-half display to beat injury-hit England 18-9 at Twickenham on Saturday.

A patched-up England side deservedly led 9-5 at halftime after two penalties and a drop goal from Jonny Wilkinson, with Australia managing only a try by livewire scrumhalf Will Genia.

The Wallabies, however, were a different side after the break and two penalties by Matt Giteau edged them ahead before a surging score in the corner by fullback Adam Ashley-Cooper completed their second successive Twickenham success.

Australia, who had lost six of their previous seven games, now face Ireland next Sunday before games against Scotland and Wales as they seek to match the grand slam achievement of the famed 1984 side.