Melbourne, Feb 14 (IANS): Co-hosts Australia hammered their way to 342/9 in their cricket World Cup opener against England at the historic Melbourne Cricket Ground here Saturday.

Opening batsman Aaron Finch (135) guided the four-time World Champions to the mammoth total with his sixth century. He got good support from skipper George Bailey (55) and all-rounder Glenn Maxwell (66).

This is the second highest total at the MCG, with the highest being 344/8 by the ICC World XI against Asia XI in January 2005.

England pacer Steven Finn picked up 5/71, with the 2015 World Cup's first hat-trick coming in the last three deliveries of the innings.

Put in to bat, Australia got off to a good start with David Warner (22) and Finch scoring at a good pace. However, two back-to-back wickets of Warner and Shane Watson (0) off pace bowler Stuart Broad brought down the scoring rate.

Australia received another jolt when in-form Steven Smith (5) was bowled by medium pacer Chris Woakes, reducing them for 70/3 in the 11th over.

However, thereon Finch struck a significant 146-run fourth-wicket partnership with skipper Bailey to steady Australia's ship. Finch hammered 12 boundaries and three sixes in his 128-ball innings.

After the duo got out, Maxwell continued the run, smashing 11 boundaries all over the ground in his 40-ball innings.

Lower down the order, Mitchell Marsh and wicketkeeper batsman Brad Haddin chipped in with 23 and 31, respectively.

Finn's hat-trick at the end brought some smiles across the English faces but their batsmen have a huge task ahead as history shows that Australia have never lost after scoring 300-plus runs while batting first.